Bug 1436059: Make XBL / Shadow DOM use AuthorStyles. r=xidorn

It's just a struct aggregating stylesheets + CascadeData, with a quirks_mode
parameter because XBL sucks so bad.

MozReview-Commit-ID: 7q99tSNXo0K

dom/xbl/nsBindingManager.cpp

@@ -787,24 +787,6 @@ nsBindingManager::MediumFeaturesChanged(nsPresContext* aPresContext,
 #endif
 }
 
-void
-nsBindingManager::UpdateBoundContentBindingsForServo(nsPresContext* aPresContext)
-{
-  MOZ_ASSERT(mDocument->IsStyledByServo(),
-             "This should be called only by servo-backend!");
-
-  RefPtr<nsPresContext> presContext = aPresContext;
-
-  EnumerateBoundContentBindings([=](nsXBLBinding* aBinding) {
-    nsXBLPrototypeBinding* protoBinding = aBinding->PrototypeBinding();
-    ServoStyleSet* styleSet = protoBinding->GetServoStyleSet();
-    if (styleSet && styleSet->StyleSheetsHaveChanged()) {
-      protoBinding->ComputeServoStyleSet(presContext);
-    }
-    return true;
-  });
-}
-
 void
 nsBindingManager::AppendAllSheets(nsTArray<StyleSheet*>& aArray)
 {

dom/xbl/nsBindingManager.h

@@ -142,10 +142,6 @@ public:
   bool MediumFeaturesChanged(nsPresContext* aPresContext,
                              mozilla::MediaFeatureChangeReason);
 
-  // Update the content bindings in mBoundContentSet due to medium features
-  // changed.
-  void UpdateBoundContentBindingsForServo(nsPresContext* aPresContext);
-
   void AppendAllSheets(nsTArray<mozilla::StyleSheet*>& aArray);
 
   void Traverse(nsIContent *aContent,

dom/xbl/nsXBLBinding.cpp

@@ -838,10 +838,10 @@ nsXBLBinding::WalkRules(nsIStyleRuleProcessor::EnumFunc aFunc, void* aData)
 }
 #endif
 
-ServoStyleSet*
-nsXBLBinding::GetServoStyleSet() const
+const RawServoAuthorStyles*
+nsXBLBinding::GetServoStyles() const
 {
-  return mPrototypeBinding->GetServoStyleSet();
+  return mPrototypeBinding->GetServoStyles();
 }
 
 // Internal helper methods ////////////////////////////////////////////////////////////////

dom/xbl/nsXBLBinding.h

@@ -23,9 +23,9 @@ class nsXBLPrototypeBinding;
 class nsIContent;
 class nsAtom;
 class nsIDocument;
+struct RawServoAuthorStyles;
 
 namespace mozilla {
-class ServoStyleSet;
 namespace dom {
 
 class ShadowRoot;
@@ -135,7 +135,7 @@ public:
   void WalkRules(nsIStyleRuleProcessor::EnumFunc aFunc, void* aData);
 #endif
 
-  mozilla::ServoStyleSet* GetServoStyleSet() const;
+  const RawServoAuthorStyles* GetServoStyles() const;
 
   static nsresult DoInitJSClass(JSContext *cx, JS::Handle<JSObject*> obj,
                                 const nsString& aClassName,

dom/xbl/nsXBLPrototypeBinding.cpp

@@ -578,20 +578,6 @@ nsXBLPrototypeBinding::GetRuleProcessor()
 }
 #endif
 
-void
-nsXBLPrototypeBinding::ComputeServoStyleSet(nsPresContext* aPresContext)
-{
-  if (mResources) {
-    mResources->ComputeServoStyleSet(aPresContext);
-  }
-}
-
-ServoStyleSet*
-nsXBLPrototypeBinding::GetServoStyleSet() const
-{
-  return mResources ? mResources->GetServoStyleSet() : nullptr;
-}
-
 void
 nsXBLPrototypeBinding::EnsureAttributeTable()
 {

dom/xbl/nsXBLPrototypeBinding.h

@@ -135,8 +135,21 @@ public:
 #ifdef MOZ_OLD_STYLE
   nsIStyleRuleProcessor* GetRuleProcessor();
 #endif
-  void ComputeServoStyleSet(nsPresContext* aPresContext);
-  mozilla::ServoStyleSet* GetServoStyleSet() const;
+  const RawServoAuthorStyles* GetServoStyles() const
+  {
+    return mResources ? mResources->GetServoStyles() : nullptr;
+  }
+  RawServoAuthorStyles* GetServoStyles()
+  {
+    return mResources
+      ? const_cast<RawServoAuthorStyles*>(mResources->GetServoStyles())
+      : nullptr;
+  }
+
+  mozilla::ServoStyleRuleMap* GetServoStyleRuleMap()
+  {
+    return mResources ? mResources->GetServoStyleRuleMap() : nullptr;
+  }
 
   nsresult FlushSkinSheets();
 

dom/xbl/nsXBLPrototypeResources.cpp

@@ -42,9 +42,6 @@ nsXBLPrototypeResources::~nsXBLPrototypeResources()
   if (mLoader) {
     mLoader->mResources = nullptr;
   }
-  if (mServoStyleSet) {
-    mServoStyleSet->Shutdown();
-  }
 }
 
 void
@@ -122,7 +119,7 @@ nsXBLPrototypeResources::FlushSkinSheets()
     // Though during unlink is fine I guess...
     if (auto* shell = doc->GetShell()) {
       MOZ_ASSERT(shell->GetPresContext());
-      ComputeServoStyleSet(shell->GetPresContext());
+      ComputeServoStyles(*shell->StyleSet()->AsServo());
     }
   } else {
 #ifdef MOZ_OLD_STYLE
@@ -190,16 +187,29 @@ nsXBLPrototypeResources::GatherRuleProcessor()
 #endif
 
 void
-nsXBLPrototypeResources::ComputeServoStyleSet(nsPresContext* aPresContext)
+nsXBLPrototypeResources::ComputeServoStyles(const ServoStyleSet& aMasterStyleSet)
 {
-  nsTArray<RefPtr<ServoStyleSheet>> sheets(mStyleSheetList.Length());
-  for (StyleSheet* sheet : mStyleSheetList) {
-    MOZ_ASSERT(sheet->IsServo(),
-               "This should only be called with Servo-flavored style backend!");
-    sheets.AppendElement(sheet->AsServo());
+  mStyleRuleMap.reset(nullptr);
+  mServoStyles.reset(Servo_AuthorStyles_Create());
+  for (auto& sheet : mStyleSheetList) {
+    Servo_AuthorStyles_AppendStyleSheet(mServoStyles.get(), sheet->AsServo());
+  }
+  Servo_AuthorStyles_Flush(mServoStyles.get(), aMasterStyleSet.RawSet());
+}
+
+ServoStyleRuleMap*
+nsXBLPrototypeResources::GetServoStyleRuleMap()
+{
+  if (!HasStyleSheets() || !mServoStyles) {
+    return nullptr;
   }
 
-  mServoStyleSet = ServoStyleSet::CreateXBLServoStyleSet(aPresContext, sheets);
+  if (!mStyleRuleMap) {
+    mStyleRuleMap = MakeUnique<ServoStyleRuleMap>();
+  }
+
+  mStyleRuleMap->EnsureTable(*this);
+  return mStyleRuleMap.get();
 }
 
 void
@@ -220,24 +230,6 @@ nsXBLPrototypeResources::InsertStyleSheetAt(size_t aIndex, StyleSheet* aSheet)
   mStyleSheetList.InsertElementAt(aIndex, aSheet);
 }
 
-StyleSheet*
-nsXBLPrototypeResources::StyleSheetAt(size_t aIndex) const
-{
-  return mStyleSheetList[aIndex];
-}
-
-size_t
-nsXBLPrototypeResources::SheetCount() const
-{
-  return mStyleSheetList.Length();
-}
-
-bool
-nsXBLPrototypeResources::HasStyleSheets() const
-{
-  return !mStyleSheetList.IsEmpty();
-}
-
 void
 nsXBLPrototypeResources::AppendStyleSheetsTo(
                                       nsTArray<StyleSheet*>& aResult) const

dom/xbl/nsXBLPrototypeResources.h

@@ -8,6 +8,7 @@
 #define nsXBLPrototypeResources_h__
 
 #include "mozilla/StyleSheet.h"
+#include "mozilla/ServoStyleRuleMap.h"
 #include "nsICSSLoaderObserver.h"
 
 class nsCSSRuleProcessor;
@@ -15,10 +16,12 @@ class nsAtom;
 class nsIContent;
 class nsXBLPrototypeBinding;
 class nsXBLResourceLoader;
+struct RawServoAuthorStyles;
 
 namespace mozilla {
 class CSSStyleSheet;
 class ServoStyleSet;
+class ServoStyleRuleMap;
 } // namespace mozilla
 
 // *********************************************************************/
@@ -45,9 +48,22 @@ public:
   void AppendStyleSheet(mozilla::StyleSheet* aSheet);
   void RemoveStyleSheet(mozilla::StyleSheet* aSheet);
   void InsertStyleSheetAt(size_t aIndex, mozilla::StyleSheet* aSheet);
-  mozilla::StyleSheet* StyleSheetAt(size_t aIndex) const;
-  size_t SheetCount() const;
-  bool HasStyleSheets() const;
+
+  mozilla::StyleSheet* StyleSheetAt(size_t aIndex) const
+  {
+    return mStyleSheetList[aIndex];
+  }
+
+  size_t SheetCount() const
+  {
+    return mStyleSheetList.Length();
+  }
+
+  bool HasStyleSheets() const
+  {
+    return !mStyleSheetList.IsEmpty();
+  }
+
   void AppendStyleSheetsTo(nsTArray<mozilla::StyleSheet*>& aResult) const;
 
 #ifdef MOZ_OLD_STYLE
@@ -61,18 +77,26 @@ public:
   nsCSSRuleProcessor* GetRuleProcessor() const { return mRuleProcessor; }
 #endif
 
+  const RawServoAuthorStyles* GetServoStyles() const
+  {
+    return mServoStyles.get();
+  }
+
+  mozilla::ServoStyleRuleMap* GetServoStyleRuleMap();
+
   // Updates the ServoStyleSet object that holds the result of cascading the
   // sheets in mStyleSheetList. Equivalent to GatherRuleProcessor(), but for
   // the Servo style backend.
-  void ComputeServoStyleSet(nsPresContext* aPresContext);
-
-  mozilla::ServoStyleSet* GetServoStyleSet() const { return mServoStyleSet.get(); }
+  void ComputeServoStyles(const mozilla::ServoStyleSet& aMasterStyleSet);
 
 private:
   // A loader object. Exists only long enough to load resources, and then it dies.
   RefPtr<nsXBLResourceLoader> mLoader;
 
   // A list of loaded stylesheets for this binding.
+  //
+  // FIXME(emilio): Remove when the old style system is gone, defer to
+  // mServoStyles.
   nsTArray<RefPtr<mozilla::StyleSheet>> mStyleSheetList;
 
 #ifdef MOZ_OLD_STYLE
@@ -82,9 +106,8 @@ private:
 
   // The result of cascading the XBL style sheets like mRuleProcessor, but
   // for the Servo style backend.
-  // XXX: We might want to design a better representation for the result of
-  // cascading the XBL style sheets, like a collection of SelectorMaps.
-  mozilla::UniquePtr<mozilla::ServoStyleSet> mServoStyleSet;
+  mozilla::UniquePtr<RawServoAuthorStyles> mServoStyles;
+  mozilla::UniquePtr<mozilla::ServoStyleRuleMap> mStyleRuleMap;
 };
 
 #endif

dom/xbl/nsXBLResourceLoader.cpp

@@ -198,8 +198,8 @@ nsXBLResourceLoader::StyleSheetLoaded(StyleSheet* aSheet,
       MOZ_CRASH("old style system disabled");
 #endif
     } else {
-      mResources->ComputeServoStyleSet(
-        mBoundDocument->GetShell()->GetPresContext());
+      mResources->ComputeServoStyles(
+        *mBoundDocument->GetShell()->StyleSet()->AsServo());
     }
 
     // XXX Check for mPendingScripts when scripts also come online.

layout/inspector/InspectorUtils.cpp

@@ -230,7 +230,6 @@ InspectorUtils::GetCSSStyleRules(GlobalObject& aGlobalObject,
     {
       ServoStyleSet* styleSet = shell->StyleSet()->AsServo();
       ServoStyleRuleMap* map = styleSet->StyleRuleMap();
-      map->EnsureTable();
       maps.AppendElement(map);
     }
 
@@ -239,9 +238,10 @@ InspectorUtils::GetCSSStyleRules(GlobalObject& aGlobalObject,
          bindingContent = bindingContent->GetBindingParent()) {
       for (nsXBLBinding* binding = bindingContent->GetXBLBinding();
            binding; binding = binding->GetBaseBinding()) {
-        if (ServoStyleSet* styleSet = binding->GetServoStyleSet()) {
-          ServoStyleRuleMap* map = styleSet->StyleRuleMap();
-          map->EnsureTable();
+        // TODO(emilio): We're going to need to figure out something for Shadow
+        // DOM and inspector, since those rules can definitely mutate and
+        // such...
+        if (auto* map = binding->PrototypeBinding()->GetServoStyleRuleMap()) {
           maps.AppendElement(map);
         }
       }

layout/inspector/ServoStyleRuleMap.cpp

@@ -18,22 +18,13 @@
 
 namespace mozilla {
 
-ServoStyleRuleMap::ServoStyleRuleMap(ServoStyleSet* aStyleSet)
-  : mStyleSet(aStyleSet)
-{
-}
-
-ServoStyleRuleMap::~ServoStyleRuleMap()
-{
-}
-
 void
-ServoStyleRuleMap::EnsureTable()
+ServoStyleRuleMap::EnsureTable(ServoStyleSet& aStyleSet)
 {
   if (!IsEmpty()) {
     return;
   }
-  mStyleSet->EnumerateStyleSheetArrays(
+  aStyleSet.EnumerateStyleSheetArrays(
     [this](const nsTArray<RefPtr<ServoStyleSheet>>& aArray) {
       for (auto& sheet : aArray) {
         FillTableFromStyleSheet(*sheet);
@@ -41,6 +32,17 @@ ServoStyleRuleMap::EnsureTable()
     });
 }
 
+void
+ServoStyleRuleMap::EnsureTable(nsXBLPrototypeResources& aXBLResources)
+{
+  if (!IsEmpty() || !aXBLResources.GetServoStyles()) {
+    return;
+  }
+  for (auto index : IntegerRange(aXBLResources.SheetCount())) {
+    FillTableFromStyleSheet(*aXBLResources.StyleSheetAt(index)->AsServo());
+  }
+}
+
 void
 ServoStyleRuleMap::SheetAdded(ServoStyleSheet& aStyleSheet)
 {

layout/inspector/ServoStyleRuleMap.h

@@ -12,6 +12,7 @@
 #include "nsDataHashtable.h"
 
 struct RawServoStyleRule;
+class nsXBLPrototypeResources;
 
 namespace mozilla {
 class ServoCSSRuleList;
@@ -23,22 +24,24 @@ class Rule;
 class ServoStyleRuleMap
 {
 public:
-  explicit ServoStyleRuleMap(ServoStyleSet* aStyleSet);
+  ServoStyleRuleMap() = default;
 
-  void EnsureTable();
-  ServoStyleRule* Lookup(const RawServoStyleRule* aRawRule) const {
+  void EnsureTable(ServoStyleSet&);
+  void EnsureTable(nsXBLPrototypeResources&);
+  ServoStyleRule* Lookup(const RawServoStyleRule* aRawRule) const
+  {
     return mTable.Get(aRawRule);
   }
 
-  void SheetAdded(ServoStyleSheet& aStyleSheet);
-  void SheetRemoved(ServoStyleSheet& aStyleSheet);
+  void SheetAdded(ServoStyleSheet&);
+  void SheetRemoved(ServoStyleSheet&);
 
   void RuleAdded(ServoStyleSheet& aStyleSheet, css::Rule&);
-  void RuleRemoved(ServoStyleSheet& aStyleSheet, css::Rule& aStyleRule);
+  void RuleRemoved(ServoStyleSheet& aStyleSheet, css::Rule&);
 
   size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;
 
-  ~ServoStyleRuleMap();
+  ~ServoStyleRuleMap() = default;
 
 private:
   // Since we would never have a document which contains no style rule,
@@ -53,7 +56,6 @@ private:
   typedef nsDataHashtable<nsPtrHashKey<const RawServoStyleRule>,
                           WeakPtr<ServoStyleRule>> Hashtable;
   Hashtable mTable;
-  ServoStyleSet* mStyleSet;
 };
 
 } // namespace mozilla

layout/style/ServoBindingList.h

@@ -43,7 +43,8 @@ SERVO_BINDING_FUNC(Servo_Element_IsPrimaryStyleReusedViaRuleNode,
 SERVO_BINDING_FUNC(Servo_InvalidateStyleForDocStateChanges,
                    void,
                    RawGeckoElementBorrowed root,
-                   const nsTArray<RawServoStyleSetBorrowed>* sets,
+                   RawServoStyleSetBorrowed doc_styles,
+                   const nsTArray<RawServoAuthorStylesBorrowed>* non_document_styles,
                    uint64_t aStatesChanged)
 
 // Styleset and Stylesheet management
@@ -83,13 +84,14 @@ SERVO_BINDING_FUNC(Servo_StyleSheet_GetOrigin, uint8_t,
 SERVO_BINDING_FUNC(Servo_StyleSet_Init, RawServoStyleSet*, RawGeckoPresContextOwned pres_context)
 SERVO_BINDING_FUNC(Servo_StyleSet_RebuildCachedData, void,
                    RawServoStyleSetBorrowed set)
+
 // We'd like to return `OriginFlags` here, but bindgen bitfield enums don't
 // work as return values with the Linux 32-bit ABI at the moment because
 // they wrap the value in a struct.
 SERVO_BINDING_FUNC(Servo_StyleSet_MediumFeaturesChanged,
                    MediumFeaturesChangedResult,
                    RawServoStyleSetBorrowed document_set,
-                   const nsTArray<mozilla::ServoStyleSet*>* non_document_sets,
+                   nsTArray<RawServoAuthorStylesBorrowedMut>* non_document_sets,
                    bool may_affect_default_style)
 // We'd like to return `OriginFlags` here, but bindgen bitfield enums don't
 // work as return values with the Linux 32-bit ABI at the moment because
@@ -173,6 +175,20 @@ SERVO_BINDING_FUNC(Servo_UACache_AddSizeOf, void,
                    mozilla::MallocSizeOf malloc_size_of,
                    mozilla::MallocSizeOf malloc_enclosing_size_of,
                    mozilla::ServoStyleSetSizes* sizes)
+
+// AuthorStyles
+SERVO_BINDING_FUNC(Servo_AuthorStyles_Create, RawServoAuthorStyles*)
+// TODO(emilio): This will need to take an optional master style set to
+// implement invalidation for Shadow DOM.
+SERVO_BINDING_FUNC(Servo_AuthorStyles_AppendStyleSheet, void,
+                   RawServoAuthorStylesBorrowedMut self,
+                   const mozilla::ServoStyleSheet* gecko_sheet)
+// TODO(emilio): This will need to take an element to implement invalidation for
+// Shadow DOM.
+SERVO_BINDING_FUNC(Servo_AuthorStyles_Flush, void,
+                   RawServoAuthorStylesBorrowedMut self,
+                   RawServoStyleSetBorrowed document_styles)
+
 SERVO_BINDING_FUNC(Servo_StyleContext_AddRef, void, ServoStyleContextBorrowed ctx);
 SERVO_BINDING_FUNC(Servo_StyleContext_Release, void, ServoStyleContextBorrowed ctx);
 

layout/style/ServoBindingTypes.h

@@ -15,6 +15,7 @@
 #include "nsStyleAutoArray.h"
 #include "nsTArray.h"
 
+struct RawServoAuthorStyles;
 struct RawServoStyleSet;
 struct RawServoSelectorList;
 struct RawServoSourceSizeList;
@@ -135,7 +136,8 @@ struct MOZ_MUST_USE_TYPE ServoStyleContextStrong
 // This is a reference to a reference of RawServoDeclarationBlock, which
 // corresponds to Option<&Arc<RawServoDeclarationBlock>> in Servo side.
 DECL_NULLABLE_BORROWED_REF_TYPE_FOR(RawServoDeclarationBlockStrong)
-
+DECL_OWNED_REF_TYPE_FOR(RawServoAuthorStyles)
+DECL_NULLABLE_BORROWED_REF_TYPE_FOR(RawServoAuthorStyles)
 DECL_OWNED_REF_TYPE_FOR(RawServoStyleSet)
 DECL_NULLABLE_BORROWED_REF_TYPE_FOR(RawServoStyleSet)
 DECL_NULLABLE_OWNED_REF_TYPE_FOR(StyleChildrenIterator)
@@ -228,6 +230,7 @@ DECL_NULLABLE_BORROWED_REF_TYPE_FOR(RawServoSourceSizeList)
   }
 
 DEFINE_BOXED_TYPE(StyleSet, RawServoStyleSet);
+DEFINE_BOXED_TYPE(AuthorStyles, RawServoAuthorStyles);
 DEFINE_BOXED_TYPE(SelectorList, RawServoSelectorList);
 DEFINE_BOXED_TYPE(SourceSizeList, RawServoSourceSizeList);
 

layout/style/ServoBindings.cpp

@@ -2434,11 +2434,10 @@ Gecko_GetXBLBinding(RawGeckoElementBorrowed aElement)
   return aElement->GetXBLBinding();
 }
 
-RawServoStyleSetBorrowedOrNull
-Gecko_XBLBinding_GetRawServoStyleSet(RawGeckoXBLBindingBorrowed aXBLBinding)
+RawServoAuthorStylesBorrowedOrNull
+Gecko_XBLBinding_GetRawServoStyles(RawGeckoXBLBindingBorrowed aXBLBinding)
 {
-  const ServoStyleSet* set = aXBLBinding->GetServoStyleSet();
-  return set ? set->RawSet() : nullptr;
+  return aXBLBinding->GetServoStyles();
 }
 
 bool

layout/style/ServoBindings.h

@@ -607,7 +607,7 @@ FontSizePrefs Gecko_GetBaseSize(nsAtom* lang);
 // XBL related functions.
 RawGeckoElementBorrowedOrNull Gecko_GetBindingParent(RawGeckoElementBorrowed aElement);
 RawGeckoXBLBindingBorrowedOrNull Gecko_GetXBLBinding(RawGeckoElementBorrowed aElement);
-RawServoStyleSetBorrowedOrNull Gecko_XBLBinding_GetRawServoStyleSet(RawGeckoXBLBindingBorrowed aXBLBinding);
+RawServoAuthorStylesBorrowedOrNull Gecko_XBLBinding_GetRawServoStyles(RawGeckoXBLBindingBorrowed aXBLBinding);
 bool Gecko_XBLBinding_InheritsStyle(RawGeckoXBLBindingBorrowed aXBLBinding);
 
 struct GeckoFontMetrics

layout/style/ServoBindings.toml

@@ -470,7 +470,6 @@ structs-types = [
     "mozilla::AnonymousCounterStyle",
     "mozilla::AtomArray",
     "mozilla::MallocSizeOf",
-    "mozilla::ServoStyleSet",
     "mozilla::OriginFlags",
     "mozilla::UniquePtr",
     "ServoRawOffsetArc",
@@ -619,6 +618,7 @@ array-types = [
 ]
 servo-owned-types = [
     { name = "RawServoStyleSet", opaque = true },
+    { name = "RawServoAuthorStyles", opaque = true },
     { name = "RawServoSelectorList", opaque = false },
     { name = "RawServoSourceSizeList", opaque = false },
     { name = "ServoElementSnapshot", opaque = false },

layout/style/ServoStyleSet.cpp

@@ -232,20 +232,19 @@ ServoStyleSet::InvalidateStyleForDocumentStateChanges(EventStates aStatesChanged
   // for XBL sheets / shadow DOM. Consider just enumerating bound content
   // instead and run invalidation individually, passing mRawSet for the UA /
   // User sheets.
-  AutoTArray<RawServoStyleSetBorrowed, 20> styleSets;
-  styleSets.AppendElement(mRawSet.get());
+  AutoTArray<RawServoAuthorStylesBorrowed, 20> xblStyles;
   // FIXME(emilio): When bug 1425759 is fixed we need to enumerate ShadowRoots
   // too.
   mDocument->BindingManager()->EnumerateBoundContentBindings(
     [&](nsXBLBinding* aBinding) {
-      if (ServoStyleSet* set = aBinding->PrototypeBinding()->GetServoStyleSet()) {
-        styleSets.AppendElement(set->RawSet());
+      if (auto* authorStyles = aBinding->PrototypeBinding()->GetServoStyles()) {
+        xblStyles.AppendElement(authorStyles);
       }
       return true;
     });
 
   Servo_InvalidateStyleForDocStateChanges(
-    root, &styleSets, aStatesChanged.ServoValue());
+    root, mRawSet.get(), &xblStyles, aStatesChanged.ServoValue());
 }
 
 static const MediaFeatureChangeReason kMediaFeaturesAffectingDefaultStyle =
@@ -263,15 +262,15 @@ static const MediaFeatureChangeReason kMediaFeaturesAffectingDefaultStyle =
 nsRestyleHint
 ServoStyleSet::MediumFeaturesChanged(MediaFeatureChangeReason aReason)
 {
-  AutoTArray<ServoStyleSet*, 20> nonDocumentStyleSets;
+  AutoTArray<RawServoAuthorStylesBorrowedMut, 20> nonDocumentStyles;
   // FIXME(emilio): When bug 1425759 is fixed we need to enumerate ShadowRoots
   // too.
   //
   // FIXME(emilio): This is broken for XBL. See bug 1406875.
   mDocument->BindingManager()->EnumerateBoundContentBindings(
     [&](nsXBLBinding* aBinding) {
-      if (ServoStyleSet* set = aBinding->PrototypeBinding()->GetServoStyleSet()) {
-        nonDocumentStyleSets.AppendElement(set);
+      if (auto* authorStyles = aBinding->PrototypeBinding()->GetServoStyles()) {
+        nonDocumentStyles.AppendElement(authorStyles);
       }
       return true;
     });
@@ -281,7 +280,7 @@ ServoStyleSet::MediumFeaturesChanged(MediaFeatureChangeReason aReason)
 
   const MediumFeaturesChangedResult result =
     Servo_StyleSet_MediumFeaturesChanged(
-      mRawSet.get(), &nonDocumentStyleSets, mayAffectDefaultStyle);
+      mRawSet.get(), &nonDocumentStyles, mayAffectDefaultStyle);
 
   const bool rulesChanged =
     result.mAffectsDocumentRules || result.mAffectsNonDocumentRules;
@@ -1461,10 +1460,13 @@ ServoStyleSet::UpdateStylist()
   if (MOZ_UNLIKELY(mStylistState & StylistState::XBLStyleSheetsDirty)) {
     MOZ_ASSERT(IsMaster(), "Only master styleset can mark XBL stylesets dirty!");
     MOZ_ASSERT(GetPresContext(), "How did they get dirty?");
-    // NOTE(emilio): This right now rebuilds the stylist in the prototype
-    // binding. That is fine, and if we wanted to be more incremental, which we
-    // probably should, we need to move away from using a StyleSet for XBL.
-    mDocument->BindingManager()->UpdateBoundContentBindingsForServo(GetPresContext());
+    mDocument->BindingManager()->EnumerateBoundContentBindings(
+      [&](nsXBLBinding* aBinding) {
+        if (auto* authorStyles = aBinding->PrototypeBinding()->GetServoStyles()) {
+          Servo_AuthorStyles_Flush(authorStyles, mRawSet.get());
+        }
+        return true;
+      });
   }
 
   mStylistState = StylistState::NotDirty;
@@ -1568,8 +1570,9 @@ ServoStyleRuleMap*
 ServoStyleSet::StyleRuleMap()
 {
   if (!mStyleRuleMap) {
-    mStyleRuleMap = MakeUnique<ServoStyleRuleMap>(this);
+    mStyleRuleMap = MakeUnique<ServoStyleRuleMap>();
   }
+  mStyleRuleMap->EnsureTable(*this);
   return mStyleRuleMap.get();
 }
 

layout/style/ServoStyleSheet.h

@@ -118,8 +118,8 @@ public:
   NS_IMETHOD StyleSheetLoaded(StyleSheet* aSheet, bool aWasAlternate,
                               nsresult aStatus) final override;
 
-  // Internal GetCssRules method which do not have security check and
-  // completelness check.
+  // Internal GetCssRules methods which do not have security check and
+  // completeness check.
   ServoCSSRuleList* GetCssRulesInternal();
 
   // Returns the stylesheet's Servo origin as an OriginFlags value.