From 3b2b29f924f467089617c92cc3ad3aa7b490383e Mon Sep 17 00:00:00 2001
From: Coroiu Cristina <ccoroiu@mozilla.com>
Date: Sat, 13 Apr 2019 11:04:15 +0300
Subject: [PATCH] Backed out changeset fd5cb917b6eb (bug 1412179) for Wr
 failures at
 /html/rendering/non-replaced-elements/the-fieldset-and-legend-elements/fieldset-vertical.html

---
 gfx/webrender_bindings/WebRenderAPI.h   |  8 --------
 layout/forms/nsFieldSetFrame.cpp        | 27 +++----------------------
 layout/reftests/box-shadow/reftest.list |  2 +-
 3 files changed, 4 insertions(+), 33 deletions(-)

diff --git a/gfx/webrender_bindings/WebRenderAPI.h b/gfx/webrender_bindings/WebRenderAPI.h
index f8975b92f352..586fa038bb69 100644
--- a/gfx/webrender_bindings/WebRenderAPI.h
+++ b/gfx/webrender_bindings/WebRenderAPI.h
@@ -642,14 +642,6 @@ class MOZ_RAII SpaceAndClipChainHelper final {
     aBuilder.mCurrentSpaceAndClipChain.space = aSpatialId;
     MOZ_GUARD_OBJECT_NOTIFIER_INIT;
   }
-  SpaceAndClipChainHelper(DisplayListBuilder& aBuilder,
-                          wr::WrClipChainId aClipChainId
-                              MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
-      : mBuilder(aBuilder),
-        mOldSpaceAndClipChain(aBuilder.mCurrentSpaceAndClipChain) {
-    aBuilder.mCurrentSpaceAndClipChain.clip_chain = aClipChainId.id;
-    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
-  }
 
   ~SpaceAndClipChainHelper() {
     mBuilder.mCurrentSpaceAndClipChain = mOldSpaceAndClipChain;
diff --git a/layout/forms/nsFieldSetFrame.cpp b/layout/forms/nsFieldSetFrame.cpp
index 4f9c25a9bde0..d54b3bad1225 100644
--- a/layout/forms/nsFieldSetFrame.cpp
+++ b/layout/forms/nsFieldSetFrame.cpp
@@ -167,36 +167,15 @@ bool nsDisplayFieldSetBorder::CreateWebRenderCommands(
   auto frame = static_cast<nsFieldSetFrame*>(mFrame);
   auto offset = ToReferenceFrame();
   nsRect rect;
-  Maybe<wr::SpaceAndClipChainHelper> clipOut;
 
   if (nsIFrame* legend = frame->GetLegend()) {
     rect = frame->VisualBorderRectRelativeToSelf() + offset;
 
+    // Legends require a "negative" clip around the text, which WR doesn't
+    // support yet.
     nsRect legendRect = legend->GetNormalRect() + offset;
-
-    // Make sure we clip all of the border in case the legend is smaller.
-    nscoord borderTopWidth = frame->GetUsedBorder().top;
-    if (legendRect.height < borderTopWidth) {
-      legendRect.height = borderTopWidth;
-      legendRect.y = offset.y;
-    }
-
     if (!legendRect.IsEmpty()) {
-      // We need to clip out the part of the border where the legend would go
-      auto appUnitsPerDevPixel = frame->PresContext()->AppUnitsPerDevPixel();
-      auto layoutRect = wr::ToRoundedLayoutRect(
-          LayoutDeviceRect::FromAppUnits(rect, appUnitsPerDevPixel));
-
-      wr::ComplexClipRegion region;
-      region.rect = wr::ToRoundedLayoutRect(
-          LayoutDeviceRect::FromAppUnits(legendRect, appUnitsPerDevPixel));
-      region.mode = wr::ClipMode::ClipOut;
-      region.radii = wr::EmptyBorderRadius();
-      nsTArray<mozilla::wr::ComplexClipRegion> array{region};
-
-      auto clip = aBuilder.DefineClip(Nothing(), layoutRect, &array, nullptr);
-      auto clipChain = aBuilder.DefineClipChain({clip});
-      clipOut.emplace(aBuilder, clipChain);
+      return false;
     }
   } else {
     rect = nsRect(offset, frame->GetRect().Size());
diff --git a/layout/reftests/box-shadow/reftest.list b/layout/reftests/box-shadow/reftest.list
index 58af6c8a2162..57cc2997f8a7 100644
--- a/layout/reftests/box-shadow/reftest.list
+++ b/layout/reftests/box-shadow/reftest.list
@@ -40,7 +40,7 @@ fuzzy(0-13,0-9445) fuzzy-if(d2d,0-13,0-10926) fuzzy-if(webrender,14-15,11263-132
 == overflow-not-scrollable-2.html overflow-not-scrollable-2-ref.html
 fuzzy-if(webrender,0-1,0-655) == 611574-1.html 611574-1-ref.html
 fuzzy-if(webrender,0-4,0-144) == 611574-2.html 611574-2-ref.html
-fuzzy-if(winWidget,0-5,0-30) fuzzy-if(skiaContent,0-16,0-10) == fieldset.html fieldset-ref.html # minor anti-aliasing problem on Windows
+fuzzy-if(winWidget,0-5,0-30) fuzzy-if(skiaContent,0-16,0-10) fuzzy-if(webrender,20-34,82-84) == fieldset.html fieldset-ref.html # minor anti-aliasing problem on Windows
 fuzzy-if(winWidget,0-5,0-30) fuzzy-if(skiaContent,0-16,0-10) fails-if(webrender) == fieldset-inset.html fieldset-inset-ref.html # minor anti-aliasing problem on Windows
 == 1178575.html 1178575-ref.html
 == 1178575-2.html 1178575-2-ref.html