Remove force-update when visual rects change

third_party/WebKit/Source/core/paint/PaintInvalidator.cpp

Index: third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp b/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
index 0548d0fafb2748aa0c73f1f1a6a4143f93290d5b..069ef463a345405925f7ae9bdf6d81099a8851e6 100644
--- a/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintInvalidator.cpp
@@ -434,17 +434,6 @@ void PaintInvalidator::invalidatePaintIfNeeded(
     context.forcedSubtreeInvalidationFlags |=
         PaintInvalidatorContext::ForcedSubtreeInvalidationChecking;
   }
-
-  // TODO(crbug.com/490725): This is a workaround for the bug, to force
-  // descendant to update visual rects on clipping change.
-  if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled() &&
-      context.oldVisualRect != context.newVisualRect
-      // Note that isLayoutView() below becomes unnecessary after the launch of
-      // root layer scrolling.
-      && (object.hasOverflowClip() || object.isLayoutView()) &&
-      !toLayoutBox(object).usesCompositedScrolling())
-    context.forcedSubtreeInvalidationFlags |=
-        PaintInvalidatorContext::ForcedSubtreeInvalidationRectUpdate;

[Xianzhu, 2017/02/21 19:31:00]

We still need to set the flag on ancestor clip change, now in PrePaintTreeWalk.

This patch fails with a modified version of
paint/invalidation/clip-unclip-and-change.html. I create a new patch based on
this CL. It includes the modified test case and fixes the issue:
https://codereview.chromium.org/2702883002/.

[chrishtr, 2017/02/27 21:15:36]

Is this test exhibiting a case where the paint invalidator context
was not properly updated for the item which changes its clip?

 }
 
 void PaintInvalidator::processPendingDelayedPaintInvalidations() {