diff --git a/dom/svg/SVGFEBlendElement.cpp b/dom/svg/SVGFEBlendElement.cpp
index 48307ad5140f..210dd01fc1f1 100644
--- a/dom/svg/SVGFEBlendElement.cpp
+++ b/dom/svg/SVGFEBlendElement.cpp
@@ -89,11 +89,9 @@ SVGFEBlendElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                            nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
   uint32_t mode = mEnumAttributes[MODE].GetAnimValue();
-  FilterPrimitiveDescription descr(PrimitiveType::Blend);
   BlendAttributes attributes;
   attributes.mBlendMode = mode;
-  descr.Attributes() = AsVariant(attributes);
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(attributes)));
 }
 
 bool
diff --git a/dom/svg/SVGFEColorMatrixElement.cpp b/dom/svg/SVGFEColorMatrixElement.cpp
index 3164415740fd..da1b29c9bcba 100644
--- a/dom/svg/SVGFEColorMatrixElement.cpp
+++ b/dom/svg/SVGFEColorMatrixElement.cpp
@@ -94,7 +94,6 @@ SVGFEColorMatrixElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   uint32_t type = mEnumAttributes[TYPE].GetAnimValue();
   const SVGNumberList &values = mNumberListAttributes[VALUES].GetAnimValue();
 
-  FilterPrimitiveDescription descr(PrimitiveType::ColorMatrix);
   ColorMatrixAttributes atts;
   if (!mNumberListAttributes[VALUES].IsExplicitlySet() &&
       (type == SVG_FECOLORMATRIX_TYPE_MATRIX ||
@@ -114,8 +113,7 @@ SVGFEColorMatrixElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
     }
   }
 
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEComponentTransferElement.cpp b/dom/svg/SVGFEComponentTransferElement.cpp
index 9356a93de0ff..882446725021 100644
--- a/dom/svg/SVGFEComponentTransferElement.cpp
+++ b/dom/svg/SVGFEComponentTransferElement.cpp
@@ -72,7 +72,6 @@ SVGFEComponentTransferElement::GetPrimitiveDescription(nsSVGFilterInstance* aIns
     }
   }
 
-  FilterPrimitiveDescription descr(PrimitiveType::ComponentTransfer);
   ComponentTransferAttributes atts;
   for (int32_t i = 0; i < 4; i++) {
     if (childForChannel[i]) {
@@ -82,8 +81,7 @@ SVGFEComponentTransferElement::GetPrimitiveDescription(nsSVGFilterInstance* aIns
         (uint8_t)SVG_FECOMPONENTTRANSFER_TYPE_IDENTITY;
     }
   }
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFECompositeElement.cpp b/dom/svg/SVGFECompositeElement.cpp
index 422015502b37..9fc0ca327c6e 100644
--- a/dom/svg/SVGFECompositeElement.cpp
+++ b/dom/svg/SVGFECompositeElement.cpp
@@ -115,7 +115,6 @@ SVGFECompositeElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                                const nsTArray<bool>& aInputsAreTainted,
                                                nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  FilterPrimitiveDescription descr(PrimitiveType::Composite);
   CompositeAttributes atts;
   uint32_t op = mEnumAttributes[OPERATOR].GetAnimValue();
   atts.mOperator = op;
@@ -126,8 +125,7 @@ SVGFECompositeElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
     atts.mCoefficients.AppendElements(k, 4);
   }
 
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEConvolveMatrixElement.cpp b/dom/svg/SVGFEConvolveMatrixElement.cpp
index 09994a902898..65db0f7c6e3a 100644
--- a/dom/svg/SVGFEConvolveMatrixElement.cpp
+++ b/dom/svg/SVGFEConvolveMatrixElement.cpp
@@ -172,7 +172,7 @@ SVGFEConvolveMatrixElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstan
                                                     const nsTArray<bool>& aInputsAreTainted,
                                                     nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  FilterPrimitiveDescription failureDescription(PrimitiveType::Empty);
+  FilterPrimitiveDescription failureDescription;
 
   const SVGNumberList &kernelMatrix =
     mNumberListAttributes[KERNELMATRIX].GetAnimValue();
@@ -238,7 +238,6 @@ SVGFEConvolveMatrixElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstan
     return failureDescription;
   }
 
-  FilterPrimitiveDescription descr(PrimitiveType::ConvolveMatrix);
   ConvolveMatrixAttributes atts;
   atts.mKernelSize = IntSize(orderX, orderY);
   atts.mKernelMatrix.AppendElements(&kernelMatrix[0], kmLength);
@@ -249,8 +248,7 @@ SVGFEConvolveMatrixElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstan
   atts.mKernelUnitLength = kernelUnitLength;
   atts.mPreserveAlpha = preserveAlpha;
 
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEDiffuseLightingElement.cpp b/dom/svg/SVGFEDiffuseLightingElement.cpp
index 66def310f150..e7fbd5a64535 100644
--- a/dom/svg/SVGFEDiffuseLightingElement.cpp
+++ b/dom/svg/SVGFEDiffuseLightingElement.cpp
@@ -69,15 +69,13 @@ SVGFEDiffuseLightingElement::GetPrimitiveDescription(nsSVGFilterInstance* aInsta
 {
   float diffuseConstant = mNumberAttributes[DIFFUSE_CONSTANT].GetAnimValue();
 
-  FilterPrimitiveDescription descr(PrimitiveType::DiffuseLighting);
   DiffuseLightingAttributes atts;
   atts.mLightingConstant = diffuseConstant;
   if (!AddLightingAttributes(&atts, aInstance)) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEDisplacementMapElement.cpp b/dom/svg/SVGFEDisplacementMapElement.cpp
index 349b7f6fb708..f898de2ca48f 100644
--- a/dom/svg/SVGFEDisplacementMapElement.cpp
+++ b/dom/svg/SVGFEDisplacementMapElement.cpp
@@ -100,24 +100,20 @@ SVGFEDisplacementMapElement::GetPrimitiveDescription(nsSVGFilterInstance* aInsta
   if (aInputsAreTainted[1]) {
     // If the map is tainted, refuse to apply the effect and act as a
     // pass-through filter instead, as required by the spec.
-    FilterPrimitiveDescription descr(PrimitiveType::Offset);
     OffsetAttributes atts;
     atts.mValue = IntPoint(0, 0);
-    descr.Attributes() = AsVariant(std::move(atts));
-    return descr;
+    return FilterPrimitiveDescription(AsVariant(std::move(atts)));
   }
 
   float scale = aInstance->GetPrimitiveNumber(SVGContentUtils::XY,
                                               &mNumberAttributes[SCALE]);
   uint32_t xChannel = mEnumAttributes[CHANNEL_X].GetAnimValue();
   uint32_t yChannel = mEnumAttributes[CHANNEL_Y].GetAnimValue();
-  FilterPrimitiveDescription descr(PrimitiveType::DisplacementMap);
   DisplacementMapAttributes atts;
   atts.mScale = scale;
   atts.mXChannel = xChannel;
   atts.mYChannel = yChannel;
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEDropShadowElement.cpp b/dom/svg/SVGFEDropShadowElement.cpp
index 6dffb4f35fc9..b43cfdfa1e7c 100644
--- a/dom/svg/SVGFEDropShadowElement.cpp
+++ b/dom/svg/SVGFEDropShadowElement.cpp
@@ -95,7 +95,7 @@ SVGFEDropShadowElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                              &mNumberPairAttributes[STD_DEV],
                                              nsSVGNumberPair::eSecond);
   if (stdX < 0 || stdY < 0) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
   IntPoint offset(int32_t(aInstance->GetPrimitiveNumber(
@@ -103,7 +103,6 @@ SVGFEDropShadowElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                   int32_t(aInstance->GetPrimitiveNumber(
                             SVGContentUtils::Y, &mNumberAttributes[DY])));
 
-  FilterPrimitiveDescription descr(PrimitiveType::DropShadow);
   DropShadowAttributes atts;
   atts.mStdDeviation = Size(stdX, stdY);
   atts.mOffset = offset;
@@ -117,8 +116,7 @@ SVGFEDropShadowElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   } else {
     atts.mColor = Color();
   }
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEFloodElement.cpp b/dom/svg/SVGFEFloodElement.cpp
index 8bd71337cfef..b338a06152f9 100644
--- a/dom/svg/SVGFEFloodElement.cpp
+++ b/dom/svg/SVGFEFloodElement.cpp
@@ -40,7 +40,6 @@ SVGFEFloodElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                            const nsTArray<bool>& aInputsAreTainted,
                                            nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  FilterPrimitiveDescription descr(PrimitiveType::Flood);
   FloodAttributes atts;
   nsIFrame* frame = GetPrimaryFrame();
   if (frame) {
@@ -51,8 +50,7 @@ SVGFEFloodElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   } else {
     atts.mColor = Color();
   }
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 //----------------------------------------------------------------------
diff --git a/dom/svg/SVGFEGaussianBlurElement.cpp b/dom/svg/SVGFEGaussianBlurElement.cpp
index 8bcb201f302b..23aa99d0d54b 100644
--- a/dom/svg/SVGFEGaussianBlurElement.cpp
+++ b/dom/svg/SVGFEGaussianBlurElement.cpp
@@ -77,14 +77,12 @@ SVGFEGaussianBlurElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance
                                              &mNumberPairAttributes[STD_DEV],
                                              nsSVGNumberPair::eSecond);
   if (stdX < 0 || stdY < 0) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
-  FilterPrimitiveDescription descr(PrimitiveType::GaussianBlur);
   GaussianBlurAttributes atts;
   atts.mStdDeviation = Size(stdX, stdY);
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEImageElement.cpp b/dom/svg/SVGFEImageElement.cpp
index ca3a87f69453..0609079a5be9 100644
--- a/dom/svg/SVGFEImageElement.cpp
+++ b/dom/svg/SVGFEImageElement.cpp
@@ -217,7 +217,7 @@ SVGFEImageElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
 {
   nsIFrame* frame = GetPrimaryFrame();
   if (!frame) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
   nsCOMPtr<imgIRequest> currentRequest;
@@ -236,7 +236,7 @@ SVGFEImageElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   }
 
   if (!image) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
   IntSize nativeSize;
@@ -252,7 +252,6 @@ SVGFEImageElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
 
   SamplingFilter samplingFilter = nsLayoutUtils::GetSamplingFilterForFrame(frame);
 
-  FilterPrimitiveDescription descr(PrimitiveType::Image);
   ImageAttributes atts;
   atts.mFilter = (uint32_t)samplingFilter;
   atts.mTransform = TM;
@@ -261,9 +260,7 @@ SVGFEImageElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   size_t imageIndex = aInputImages.Length();
   aInputImages.AppendElement(image);
   atts.mInputIndex = (uint32_t)imageIndex;
-  descr.Attributes() = AsVariant(std::move(atts));
-
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEMergeElement.cpp b/dom/svg/SVGFEMergeElement.cpp
index 49a0a82daaed..05e653724a58 100644
--- a/dom/svg/SVGFEMergeElement.cpp
+++ b/dom/svg/SVGFEMergeElement.cpp
@@ -34,7 +34,7 @@ SVGFEMergeElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                            const nsTArray<bool>& aInputsAreTainted,
                                            nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  return FilterPrimitiveDescription(PrimitiveType::Merge);
+  return FilterPrimitiveDescription(AsVariant(MergeAttributes()));
 }
 
 void
diff --git a/dom/svg/SVGFEMorphologyElement.cpp b/dom/svg/SVGFEMorphologyElement.cpp
index 73e0e1c5295f..e093e06740e0 100644
--- a/dom/svg/SVGFEMorphologyElement.cpp
+++ b/dom/svg/SVGFEMorphologyElement.cpp
@@ -120,12 +120,10 @@ SVGFEMorphologyElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
 {
   int32_t rx, ry;
   GetRXY(&rx, &ry, *aInstance);
-  FilterPrimitiveDescription descr(PrimitiveType::Morphology);
   MorphologyAttributes atts;
   atts.mRadii = Size(rx, ry);
   atts.mOperator = (uint32_t)mEnumAttributes[OPERATOR].GetAnimValue();
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFEOffsetElement.cpp b/dom/svg/SVGFEOffsetElement.cpp
index 4f545cff386b..4e7fcbb10e99 100644
--- a/dom/svg/SVGFEOffsetElement.cpp
+++ b/dom/svg/SVGFEOffsetElement.cpp
@@ -66,15 +66,13 @@ SVGFEOffsetElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                             const nsTArray<bool>& aInputsAreTainted,
                                             nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  FilterPrimitiveDescription descr(PrimitiveType::Offset);
   OffsetAttributes atts;
   IntPoint offset(int32_t(aInstance->GetPrimitiveNumber(
                             SVGContentUtils::X, &mNumberAttributes[DX])),
                   int32_t(aInstance->GetPrimitiveNumber(
                             SVGContentUtils::Y, &mNumberAttributes[DY])));
   atts.mValue = offset;
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFESpecularLightingElement.cpp b/dom/svg/SVGFESpecularLightingElement.cpp
index b008d1241fa5..14f1af278bb3 100644
--- a/dom/svg/SVGFESpecularLightingElement.cpp
+++ b/dom/svg/SVGFESpecularLightingElement.cpp
@@ -79,19 +79,17 @@ SVGFESpecularLightingElement::GetPrimitiveDescription(nsSVGFilterInstance* aInst
 
   // specification defined range (15.22)
   if (specularExponent < 1 || specularExponent > 128) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
-  FilterPrimitiveDescription descr(PrimitiveType::SpecularLighting);
   SpecularLightingAttributes atts;
   atts.mLightingConstant = specularConstant;
   atts.mSpecularExponent = specularExponent;
   if (!AddLightingAttributes(static_cast<DiffuseLightingAttributes*>(&atts), aInstance)) {
-    return FilterPrimitiveDescription(PrimitiveType::Empty);
+    return FilterPrimitiveDescription();
   }
 
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/dom/svg/SVGFETileElement.cpp b/dom/svg/SVGFETileElement.cpp
index 0b39a8a91067..46419887b344 100644
--- a/dom/svg/SVGFETileElement.cpp
+++ b/dom/svg/SVGFETileElement.cpp
@@ -54,7 +54,7 @@ SVGFETileElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                                           const nsTArray<bool>& aInputsAreTainted,
                                           nsTArray<RefPtr<SourceSurface>>& aInputImages)
 {
-  return FilterPrimitiveDescription(PrimitiveType::Tile);
+  return FilterPrimitiveDescription(AsVariant(TileAttributes()));
 }
 
 bool
diff --git a/dom/svg/SVGFETurbulenceElement.cpp b/dom/svg/SVGFETurbulenceElement.cpp
index 6f0f98c87d1f..108cbeb5eca6 100644
--- a/dom/svg/SVGFETurbulenceElement.cpp
+++ b/dom/svg/SVGFETurbulenceElement.cpp
@@ -136,13 +136,11 @@ SVGFETurbulenceElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
     // A base frequency of zero results in transparent black for
     // type="turbulence" and in 50% alpha 50% gray for type="fractalNoise".
     if (type == SVG_TURBULENCE_TYPE_TURBULENCE) {
-      return FilterPrimitiveDescription(PrimitiveType::Empty);
+      return FilterPrimitiveDescription();
     }
-    FilterPrimitiveDescription descr(PrimitiveType::Flood);
     FloodAttributes atts;
     atts.mColor = Color(0.5, 0.5, 0.5, 0.5);
-    descr.Attributes() = AsVariant(std::move(atts));
-    return descr;
+    return FilterPrimitiveDescription(AsVariant(std::move(atts)));
   }
 
   // We interpret the base frequency as relative to user space units. In other
@@ -162,7 +160,6 @@ SVGFETurbulenceElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
                               fY == 0 ? 0 : (1 / firstPeriodInFilterSpace.height));
   gfxPoint offset = firstPeriodInFilterSpace.TopLeft();
 
-  FilterPrimitiveDescription descr(PrimitiveType::Turbulence);
   TurbulenceAttributes atts;
   atts.mOffset = IntPoint::Truncate(offset.x, offset.y);
   atts.mBaseFrequency = frequencyInFilterSpace;
@@ -170,8 +167,7 @@ SVGFETurbulenceElement::GetPrimitiveDescription(nsSVGFilterInstance* aInstance,
   atts.mOctaves = octaves;
   atts.mStitchable = stitch == SVG_STITCHTYPE_STITCH;
   atts.mType = type;
-  descr.Attributes() = AsVariant(std::move(atts));
-  return descr;
+  return FilterPrimitiveDescription(AsVariant(std::move(atts)));
 }
 
 bool
diff --git a/gfx/ipc/GfxMessageUtils.h b/gfx/ipc/GfxMessageUtils.h
index 67e4321fabd2..6618ba039fbe 100644
--- a/gfx/ipc/GfxMessageUtils.h
+++ b/gfx/ipc/GfxMessageUtils.h
@@ -253,14 +253,6 @@ struct ParamTraits<mozilla::gfx::FeatureStatus>
              mozilla::gfx::FeatureStatus::LAST>
 {};
 
-template <>
-struct ParamTraits<mozilla::gfx::PrimitiveType>
-  : public ContiguousEnumSerializer<
-             mozilla::gfx::PrimitiveType,
-             mozilla::gfx::PrimitiveType::Empty,
-             mozilla::gfx::PrimitiveType::Max>
-{};
-
 template <>
 struct ParamTraits<mozilla::gfx::LightType>
   : public ContiguousEnumSerializer<
@@ -1181,7 +1173,6 @@ struct ParamTraits<mozilla::gfx::FilterPrimitiveDescription>
 
   static void Write(Message* aMsg, const paramType& aParam)
   {
-    WriteParam(aMsg, aParam.Type());
     WriteParam(aMsg, aParam.PrimitiveSubregion());
     WriteParam(aMsg, aParam.FilterSpaceBounds());
     WriteParam(aMsg, aParam.IsTainted());
@@ -1196,14 +1187,12 @@ struct ParamTraits<mozilla::gfx::FilterPrimitiveDescription>
 
   static bool Read(const Message* aMsg, PickleIterator* aIter, paramType* aResult)
   {
-    mozilla::gfx::PrimitiveType type;
     mozilla::gfx::IntRect primitiveSubregion;
     mozilla::gfx::IntRect filterSpaceBounds;
     bool isTainted = false;
     mozilla::gfx::ColorSpace outputColorSpace;
     size_t numberOfInputs = 0;
-    if (!ReadParam(aMsg, aIter, &type) ||
-        !ReadParam(aMsg, aIter, &primitiveSubregion) ||
+    if (!ReadParam(aMsg, aIter, &primitiveSubregion) ||
         !ReadParam(aMsg, aIter, &filterSpaceBounds) ||
         !ReadParam(aMsg, aIter, &isTainted) ||
         !ReadParam(aMsg, aIter, &outputColorSpace) ||
@@ -1211,7 +1200,6 @@ struct ParamTraits<mozilla::gfx::FilterPrimitiveDescription>
       return false;
     }
 
-    aResult->SetType(type);
     aResult->SetPrimitiveSubregion(primitiveSubregion);
     aResult->SetFilterSpaceBounds(filterSpaceBounds);
     aResult->SetIsTainted(isTainted);
diff --git a/gfx/src/FilterSupport.cpp b/gfx/src/FilterSupport.cpp
index 2856d4808917..348c806bdef5 100644
--- a/gfx/src/FilterSupport.cpp
+++ b/gfx/src/FilterSupport.cpp
@@ -1091,7 +1091,7 @@ FilterNodeFromPrimitiveDescription(const FilterPrimitiveDescription& aDescriptio
     already_AddRefed<FilterNode> match(const DiffuseLightingAttributes& aLighting)
     {
       bool isSpecular =
-        mDescription.Type() == PrimitiveType::SpecularLighting;
+        mDescription.Attributes().is<SpecularLightingAttributes>();
 
       if (aLighting.mLightType == LightType::None) {
         return nullptr;
@@ -1230,28 +1230,25 @@ InputAlphaModelForPrimitive(const FilterPrimitiveDescription& aDescr,
                             int32_t aInputIndex,
                             AlphaModel aOriginalAlphaModel)
 {
-  switch (aDescr.Type()) {
-    case PrimitiveType::Tile:
-    case PrimitiveType::Offset:
-    case PrimitiveType::ToAlpha:
+  const PrimitiveAttributes& atts = aDescr.Attributes();
+  if (atts.is<TileAttributes>() ||
+      atts.is<OffsetAttributes>() ||
+      atts.is<ToAlphaAttributes>()) {
       return aOriginalAlphaModel;
-
-    case PrimitiveType::ColorMatrix:
-    case PrimitiveType::ComponentTransfer:
-      return AlphaModel::Unpremultiplied;
-
-    case PrimitiveType::DisplacementMap:
-      return aInputIndex == 0 ?
-        AlphaModel::Premultiplied : AlphaModel::Unpremultiplied;
-
-    case PrimitiveType::ConvolveMatrix:
-      MOZ_ASSERT(aDescr.Attributes().is<ConvolveMatrixAttributes>());
-      return aDescr.Attributes().as<ConvolveMatrixAttributes>().mPreserveAlpha ?
-        AlphaModel::Unpremultiplied : AlphaModel::Premultiplied;
-
-    default:
-      return AlphaModel::Premultiplied;
   }
+  if (atts.is<ColorMatrixAttributes>() ||
+      atts.is<ComponentTransferAttributes>()) {
+    return AlphaModel::Unpremultiplied;
+  }
+  if (atts.is<DisplacementMapAttributes>()) {
+    return aInputIndex == 0 ?
+      AlphaModel::Premultiplied : AlphaModel::Unpremultiplied;
+  }
+  if (atts.is<ConvolveMatrixAttributes>()) {
+    return atts.as<ConvolveMatrixAttributes>().mPreserveAlpha ?
+      AlphaModel::Unpremultiplied : AlphaModel::Premultiplied;
+  }
+  return AlphaModel::Premultiplied;
 }
 
 static AlphaModel
@@ -2040,24 +2037,21 @@ FilterSupport::ComputeSourceNeededRegions(const FilterDescription& aFilter,
 // FilterPrimitiveDescription
 
 FilterPrimitiveDescription::FilterPrimitiveDescription()
- : mType(PrimitiveType::Empty)
- , mAttributes(EmptyAttributes())
+ : mAttributes(EmptyAttributes())
  , mOutputColorSpace(ColorSpace::SRGB)
  , mIsTainted(false)
 {
 }
 
-FilterPrimitiveDescription::FilterPrimitiveDescription(PrimitiveType aType)
- : mType(aType)
- , mAttributes(EmptyAttributes())
+FilterPrimitiveDescription::FilterPrimitiveDescription(PrimitiveAttributes&& aAttributes)
+ : mAttributes(std::move(aAttributes))
  , mOutputColorSpace(ColorSpace::SRGB)
  , mIsTainted(false)
 {
 }
 
 FilterPrimitiveDescription::FilterPrimitiveDescription(const FilterPrimitiveDescription& aOther)
- : mType(aOther.mType)
- , mAttributes(aOther.mAttributes)
+ : mAttributes(aOther.mAttributes)
  , mInputPrimitives(aOther.mInputPrimitives)
  , mFilterPrimitiveSubregion(aOther.mFilterPrimitiveSubregion)
  , mFilterSpaceBounds(aOther.mFilterSpaceBounds)
@@ -2071,7 +2065,6 @@ FilterPrimitiveDescription&
 FilterPrimitiveDescription::operator=(const FilterPrimitiveDescription& aOther)
 {
   if (this != &aOther) {
-    mType = aOther.mType;
     mAttributes = aOther.mAttributes;
     mInputPrimitives = aOther.mInputPrimitives;
     mFilterPrimitiveSubregion = aOther.mFilterPrimitiveSubregion;
@@ -2084,8 +2077,7 @@ FilterPrimitiveDescription::operator=(const FilterPrimitiveDescription& aOther)
 }
 
 FilterPrimitiveDescription::FilterPrimitiveDescription(FilterPrimitiveDescription&& aOther)
- : mType(aOther.mType)
- , mAttributes(std::move(aOther.mAttributes))
+ : mAttributes(std::move(aOther.mAttributes))
  , mInputPrimitives(std::move(aOther.mInputPrimitives))
  , mFilterPrimitiveSubregion(aOther.mFilterPrimitiveSubregion)
  , mFilterSpaceBounds(aOther.mFilterSpaceBounds)
@@ -2099,7 +2091,6 @@ FilterPrimitiveDescription&
 FilterPrimitiveDescription::operator=(FilterPrimitiveDescription&& aOther)
 {
   if (this != &aOther) {
-    mType = aOther.mType;
     mAttributes = std::move(aOther.mAttributes);
     mInputPrimitives = std::move(aOther.mInputPrimitives);
     mFilterPrimitiveSubregion = aOther.mFilterPrimitiveSubregion;
@@ -2114,8 +2105,7 @@ FilterPrimitiveDescription::operator=(FilterPrimitiveDescription&& aOther)
 bool
 FilterPrimitiveDescription::operator==(const FilterPrimitiveDescription& aOther) const
 {
-  return mType == aOther.mType &&
-    mFilterPrimitiveSubregion.IsEqualInterior(aOther.mFilterPrimitiveSubregion) &&
+  return mFilterPrimitiveSubregion.IsEqualInterior(aOther.mFilterPrimitiveSubregion) &&
     mFilterSpaceBounds.IsEqualInterior(aOther.mFilterSpaceBounds) &&
     mOutputColorSpace == aOther.mOutputColorSpace &&
     mIsTainted == aOther.mIsTainted &&
diff --git a/gfx/src/FilterSupport.h b/gfx/src/FilterSupport.h
index 9f2690c9b1e0..5afc12dacbc1 100644
--- a/gfx/src/FilterSupport.h
+++ b/gfx/src/FilterSupport.h
@@ -94,30 +94,6 @@ struct FilterAttribute;
 // Limits
 const float kMaxStdDeviation = 500;
 
-enum class PrimitiveType {
-  Empty = 0,
-  Blend,
-  Morphology,
-  ColorMatrix,
-  Flood,
-  Tile,
-  ComponentTransfer,
-  Opacity,
-  ConvolveMatrix,
-  Offset,
-  DisplacementMap,
-  Turbulence,
-  Composite,
-  Merge,
-  Image,
-  GaussianBlur,
-  DropShadow,
-  DiffuseLighting,
-  SpecularLighting,
-  ToAlpha,
-  Max
-};
-
 // Simple PrimitiveAttributes:
 
 struct EmptyAttributes {
@@ -468,14 +444,12 @@ public:
   };
 
   FilterPrimitiveDescription();
-  explicit FilterPrimitiveDescription(PrimitiveType aType);
+  explicit FilterPrimitiveDescription(PrimitiveAttributes&& aAttributes);
   FilterPrimitiveDescription(FilterPrimitiveDescription&& aOther);
   FilterPrimitiveDescription& operator=(FilterPrimitiveDescription&& aOther);
   FilterPrimitiveDescription(const FilterPrimitiveDescription& aOther);
   FilterPrimitiveDescription& operator=(const FilterPrimitiveDescription& aOther);
 
-  PrimitiveType Type() const { return mType; }
-  void SetType(PrimitiveType aType) { mType = aType; }
   const PrimitiveAttributes& Attributes() const { return mAttributes; }
   PrimitiveAttributes& Attributes() { return mAttributes; }
 
@@ -537,7 +511,6 @@ public:
   }
 
 private:
-  PrimitiveType mType;
   PrimitiveAttributes mAttributes;
   nsTArray<int32_t> mInputPrimitives;
   IntRect mFilterPrimitiveSubregion;
diff --git a/layout/svg/nsCSSFilterInstance.cpp b/layout/svg/nsCSSFilterInstance.cpp
index 3359c86e4fd5..b91f35ca6868 100644
--- a/layout/svg/nsCSSFilterInstance.cpp
+++ b/layout/svg/nsCSSFilterInstance.cpp
@@ -44,68 +44,38 @@ nsresult
 nsCSSFilterInstance::BuildPrimitives(nsTArray<FilterPrimitiveDescription>& aPrimitiveDescrs,
                                      bool aInputIsTainted)
 {
-  FilterPrimitiveDescription descr;
+  FilterPrimitiveDescription descr = CreatePrimitiveDescription(aPrimitiveDescrs,
+                                                                aInputIsTainted);
   nsresult result;
-
   switch(mFilter.GetType()) {
     case NS_STYLE_FILTER_BLUR:
-      descr = CreatePrimitiveDescription(PrimitiveType::GaussianBlur,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForBlur(descr);
       break;
     case NS_STYLE_FILTER_BRIGHTNESS:
-      descr = CreatePrimitiveDescription(PrimitiveType::ComponentTransfer,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForBrightness(descr);
       break;
     case NS_STYLE_FILTER_CONTRAST:
-      descr = CreatePrimitiveDescription(PrimitiveType::ComponentTransfer,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForContrast(descr);
       break;
     case NS_STYLE_FILTER_DROP_SHADOW:
-      descr = CreatePrimitiveDescription(PrimitiveType::DropShadow,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForDropShadow(descr);
       break;
     case NS_STYLE_FILTER_GRAYSCALE:
-      descr = CreatePrimitiveDescription(PrimitiveType::ColorMatrix,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForGrayscale(descr);
       break;
     case NS_STYLE_FILTER_HUE_ROTATE:
-      descr = CreatePrimitiveDescription(PrimitiveType::ColorMatrix,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForHueRotate(descr);
       break;
     case NS_STYLE_FILTER_INVERT:
-      descr = CreatePrimitiveDescription(PrimitiveType::ComponentTransfer,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForInvert(descr);
       break;
     case NS_STYLE_FILTER_OPACITY:
-      descr = CreatePrimitiveDescription(PrimitiveType::Opacity,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForOpacity(descr);
       break;
     case NS_STYLE_FILTER_SATURATE:
-      descr = CreatePrimitiveDescription(PrimitiveType::ColorMatrix,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForSaturate(descr);
       break;
     case NS_STYLE_FILTER_SEPIA:
-      descr = CreatePrimitiveDescription(PrimitiveType::ColorMatrix,
-                                         aPrimitiveDescrs,
-                                         aInputIsTainted);
       result = SetAttributesForSepia(descr);
       break;
     default:
@@ -127,10 +97,9 @@ nsCSSFilterInstance::BuildPrimitives(nsTArray<FilterPrimitiveDescription>& aPrim
 }
 
 FilterPrimitiveDescription
-nsCSSFilterInstance::CreatePrimitiveDescription(PrimitiveType aType,
-                                                const nsTArray<FilterPrimitiveDescription>& aPrimitiveDescrs,
+nsCSSFilterInstance::CreatePrimitiveDescription(const nsTArray<FilterPrimitiveDescription>& aPrimitiveDescrs,
                                                 bool aInputIsTainted) {
-  FilterPrimitiveDescription descr(aType);
+  FilterPrimitiveDescription descr;
   int32_t inputIndex = GetLastResultIndex(aPrimitiveDescrs);
   descr.SetInputPrimitive(0, inputIndex);
   descr.SetIsTainted(inputIndex < 0 ? aInputIsTainted : aPrimitiveDescrs[inputIndex].IsTainted());
diff --git a/layout/svg/nsCSSFilterInstance.h b/layout/svg/nsCSSFilterInstance.h
index a9581bcf80ed..25eac50fd0bd 100644
--- a/layout/svg/nsCSSFilterInstance.h
+++ b/layout/svg/nsCSSFilterInstance.h
@@ -27,7 +27,6 @@ class nsCSSFilterInstance
   typedef mozilla::gfx::Color Color;
   typedef mozilla::gfx::FilterPrimitiveDescription FilterPrimitiveDescription;
   typedef mozilla::gfx::IntPoint IntPoint;
-  typedef mozilla::gfx::PrimitiveType PrimitiveType;
   typedef mozilla::gfx::Size Size;
 
 public:
@@ -67,8 +66,7 @@ private:
    * Returns a new FilterPrimitiveDescription with its basic properties set up.
    * See the comment above BuildPrimitives for the meaning of aInputIsTainted.
    */
-  FilterPrimitiveDescription CreatePrimitiveDescription(PrimitiveType aType,
-                                                        const nsTArray<FilterPrimitiveDescription>& aPrimitiveDescrs,
+  FilterPrimitiveDescription CreatePrimitiveDescription(const nsTArray<FilterPrimitiveDescription>& aPrimitiveDescrs,
                                                         bool aInputIsTainted);
 
   /**
diff --git a/layout/svg/nsSVGFilterInstance.cpp b/layout/svg/nsSVGFilterInstance.cpp
index 1c284e0ed5ef..bf94ae2179ee 100644
--- a/layout/svg/nsSVGFilterInstance.cpp
+++ b/layout/svg/nsSVGFilterInstance.cpp
@@ -309,7 +309,7 @@ nsSVGFilterInstance::GetOrCreateSourceAlphaIndex(nsTArray<FilterPrimitiveDescrip
 
   // Otherwise, create a primitive description to turn the previous filter's
   // output into a SourceAlpha input.
-  FilterPrimitiveDescription descr(PrimitiveType::ToAlpha);
+  FilterPrimitiveDescription descr(AsVariant(ToAlphaAttributes()));
   descr.SetInputPrimitive(0, mSourceGraphicIndex);
 
   const FilterPrimitiveDescription& sourcePrimitiveDescr =
@@ -321,7 +321,7 @@ nsSVGFilterInstance::GetOrCreateSourceAlphaIndex(nsTArray<FilterPrimitiveDescrip
   descr.SetInputColorSpace(0, colorSpace);
   descr.SetOutputColorSpace(colorSpace);
 
-  aPrimitiveDescrs.AppendElement(descr);
+  aPrimitiveDescrs.AppendElement(std::move(descr));
   mSourceAlphaIndex = aPrimitiveDescrs.Length() - 1;
   mSourceAlphaAvailable = true;
   return mSourceAlphaIndex;