Add a dirty bit for updateDescendantDependentFlags.

Source/core/paint/DeprecatedPaintLayer.cpp

Index: Source/core/paint/DeprecatedPaintLayer.cpp
diff --git a/Source/core/paint/DeprecatedPaintLayer.cpp b/Source/core/paint/DeprecatedPaintLayer.cpp
index df5e4e0e0d7c89755b6f7f0906f0d214079927ea..81f29ebe4fcb059286468123362ea893c1637fc0 100644
--- a/Source/core/paint/DeprecatedPaintLayer.cpp
+++ b/Source/core/paint/DeprecatedPaintLayer.cpp
@@ -651,6 +651,7 @@ LayoutRect DeprecatedPaintLayer::computePaintInvalidationRect(const LayoutObject
 
 void DeprecatedPaintLayer::dirtyVisibleContentStatus()
 {
+    compositor()->setNeedsUpdateDescendantDependentFlags();
     m_visibleContentStatusDirty = true;
     if (parent())
         parent()->dirtyAncestorChainVisibleDescendantStatus();
@@ -667,10 +668,11 @@ void DeprecatedPaintLayer::potentiallyDirtyVisibleContentStatus(EVisibility visi
 
 void DeprecatedPaintLayer::dirtyAncestorChainVisibleDescendantStatus()
 {
+    compositor()->setNeedsUpdateDescendantDependentFlags();
+
     for (DeprecatedPaintLayer* layer = this; layer; layer = layer->parent()) {
         if (layer->m_visibleDescendantStatusDirty)
             break;
-
         layer->m_visibleDescendantStatusDirty = true;
     }
 }
@@ -697,22 +699,6 @@ void DeprecatedPaintLayer::updateScrollingStateAfterCompositingChange()
     }
 }
 
-// The descendant-dependent flags system is badly broken because we clean dirty
-// bits in upward tree walks, which means we need to call updateDescendantDependentFlags
-// at every node in the tree to fully clean all the dirty bits. While we'll in
-// the process of fixing this issue, updateDescendantDependentFlagsForEntireSubtree
-// provides a big hammer for actually cleaning all the dirty bits in a subtree.
-//
-// FIXME: Remove this function once the descendant-dependent flags system keeps
-// its dirty bits scoped to subtrees.
-void DeprecatedPaintLayer::updateDescendantDependentFlagsForEntireSubtree()
-{
-    updateDescendantDependentFlags();
-
-    for (DeprecatedPaintLayer* child = firstChild(); child; child = child->nextSibling())
-        child->updateDescendantDependentFlagsForEntireSubtree();
-}
-
 void DeprecatedPaintLayer::updateDescendantDependentFlags()
 {
     if (m_visibleDescendantStatusDirty) {