Revert "Fix border radius on composited children."

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

Index: third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
index 2d831e1eefae11322c7b37ed69ae379969ef3b56..d238b392794828ea16985bb04527cb2ee7e481a6 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
@@ -202,7 +202,7 @@ CompositedLayerMapping::~CompositedLayerMapping() {
     }
   }
 
-  updateClippingLayers(false, false, false);
+  updateClippingLayers(false, false);
   updateOverflowControlsLayers(false, false, false, false);
   updateChildTransformLayer(false);
   updateForegroundLayer(false);
@@ -246,7 +246,6 @@ void CompositedLayerMapping::destroyGraphicsLayers() {
     m_graphicsLayer->removeFromParent();
 
   m_ancestorClippingLayer = nullptr;
-  m_ancestorClippingMaskLayer = nullptr;
   m_graphicsLayer = nullptr;
   m_foregroundLayer = nullptr;
   m_backgroundLayer = nullptr;
@@ -473,34 +472,29 @@ void CompositedLayerMapping::updateCompositingReasons() {
       m_owningLayer.getSquashingDisallowedReasons());
 }
 
-void CompositedLayerMapping::
-    owningLayerClippedOrMaskedByLayerNotAboveCompositedAncestor(
-        const PaintLayer* scrollParent,
-        bool& owningLayerIsClipped,
-        bool& owningLayerIsMasked) {
-  owningLayerIsClipped = false;
-  owningLayerIsMasked = false;
-
+bool CompositedLayerMapping::
+    owningLayerClippedByLayerNotAboveCompositedAncestor(
+        const PaintLayer* scrollParent) {
   if (!m_owningLayer.parent())
-    return;
+    return false;
 
   const PaintLayer* compositingAncestor =
       m_owningLayer.enclosingLayerWithCompositedLayerMapping(ExcludeSelf);
   if (!compositingAncestor)
-    return;
+    return false;
 
   const LayoutObject* clippingContainer = m_owningLayer.clippingContainer();
   if (!clippingContainer)
-    return;
+    return false;
 
   if (clippingContainer->enclosingLayer() == scrollParent)
-    return;
+    return false;
 
   if (clippingContainer->enclosingLayer()->hasRootScrollerAsDescendant())
-    return;
+    return false;
 
   if (compositingAncestor->layoutObject()->isDescendantOf(clippingContainer))
-    return;
+    return false;
 
   // We ignore overflow clip here; we want composited overflow content to
   // behave as if it lives in an unclipped universe so it can prepaint, etc.
@@ -515,14 +509,7 @@ void CompositedLayerMapping::
   clipRectsContext.setIgnoreOverflowClip();
   IntRect parentClipRect = pixelSnappedIntRect(
       m_owningLayer.clipper().backgroundClipRect(clipRectsContext).rect());
-  owningLayerIsClipped = parentClipRect != LayoutRect::infiniteIntRect();
-
-  // TODO(schenney): CSS clips are not applied to composited children, and
-  // should be via mask or by compositing the parent too.
-  // https://bugs.chromium.org/p/chromium/issues/detail?id=615870
-  DCHECK(clippingContainer->style());
-  owningLayerIsMasked =
-      owningLayerIsClipped && clippingContainer->style()->hasBorderRadius();
+  return parentClipRect != LayoutRect::infiniteIntRect();
 }
 
 const PaintLayer* CompositedLayerMapping::scrollParent() {
@@ -578,12 +565,10 @@ bool CompositedLayerMapping::updateGraphicsLayerConfiguration() {
   // layoutObject hierarchy, but a sibling in the z-order hierarchy. Further,
   // that sibling need not be composited at all. In such scenarios, an ancestor
   // clipping layer is necessary to apply the composited clip for this layer.
-  bool needsAncestorClip = false;
-  bool needsAncestorClippingMask = false;
-  owningLayerClippedOrMaskedByLayerNotAboveCompositedAncestor(
-      scrollParent, needsAncestorClip, needsAncestorClippingMask);
-  if (updateClippingLayers(needsAncestorClip, needsAncestorClippingMask,
-                           needsDescendantsClippingLayer))
+  bool needsAncestorClip =
+      owningLayerClippedByLayerNotAboveCompositedAncestor(scrollParent);
+
+  if (updateClippingLayers(needsAncestorClip, needsDescendantsClippingLayer))
     layerConfigChanged = true;
 
   bool scrollingConfigChanged = false;
@@ -1115,13 +1100,6 @@ void CompositedLayerMapping::updateAncestorClippingLayerGeometry(
   m_ancestorClippingLayer->setOffsetFromLayoutObject(
       parentClipRect.location() - snappedOffsetFromCompositedAncestor);
 
-  if (m_ancestorClippingMaskLayer) {
-    m_ancestorClippingMaskLayer->setOffsetFromLayoutObject(
-        m_ancestorClippingLayer->offsetFromLayoutObject());
-    m_ancestorClippingMaskLayer->setSize(m_ancestorClippingLayer->size());
-    m_ancestorClippingMaskLayer->setNeedsDisplay();
-  }
-
   // The primary layer is then parented in, and positioned relative to this
   // clipping layer.
   graphicsLayerParentLocation = parentClipRect.location();
@@ -1673,9 +1651,6 @@ void CompositedLayerMapping::updateDrawsContent() {
   if (m_decorationOutlineLayer)
     m_decorationOutlineLayer->setDrawsContent(true);
 
-  if (m_ancestorClippingMaskLayer)
-    m_ancestorClippingMaskLayer->setDrawsContent(true);
-
   if (m_maskLayer)
     m_maskLayer->setDrawsContent(true);
 
@@ -1693,10 +1668,8 @@ void CompositedLayerMapping::updateChildrenTransform() {
 }
 
 // Return true if the layers changed.
-bool CompositedLayerMapping::updateClippingLayers(
-    bool needsAncestorClip,
-    bool needsAncestorClippingMask,
-    bool needsDescendantClip) {
+bool CompositedLayerMapping::updateClippingLayers(bool needsAncestorClip,
+                                                  bool needsDescendantClip) {
   bool layersChanged = false;
 
   if (needsAncestorClip) {
@@ -1708,32 +1681,11 @@ bool CompositedLayerMapping::updateClippingLayers(
       layersChanged = true;
     }
   } else if (m_ancestorClippingLayer) {
-    if (m_ancestorClippingMaskLayer) {
-      m_ancestorClippingMaskLayer->removeFromParent();
-      m_ancestorClippingMaskLayer = nullptr;
-    }
     m_ancestorClippingLayer->removeFromParent();
     m_ancestorClippingLayer = nullptr;
     layersChanged = true;
   }
 
-  if (needsAncestorClippingMask) {
-    DCHECK(m_ancestorClippingLayer);
-    if (!m_ancestorClippingMaskLayer) {
-      m_ancestorClippingMaskLayer =
-          createGraphicsLayer(CompositingReasonLayerForAncestorClippingMask);
-      m_ancestorClippingMaskLayer->setPaintingPhase(
-          GraphicsLayerPaintAncestorClippingMask);
-      m_ancestorClippingLayer->setMaskLayer(m_ancestorClippingMaskLayer.get());
-      layersChanged = true;
-    }
-  } else if (m_ancestorClippingMaskLayer) {
-    m_ancestorClippingMaskLayer->removeFromParent();
-    m_ancestorClippingMaskLayer = nullptr;
-    m_ancestorClippingLayer->setMaskLayer(nullptr);
-    layersChanged = true;
-  }
-
   if (needsDescendantClip) {
     // We don't need a child containment layer if we're the main frame layout
     // view layer. It's redundant as the frame clip above us will handle this
@@ -1963,10 +1915,6 @@ static void ApplyToGraphicsLayers(const CompositedLayerMapping* mapping,
        (mode & ApplyToNonScrollingContentLayers)) &&
       mapping->childClippingMaskLayer())
     f(mapping->childClippingMaskLayer());
-  if (((mode & ApplyToMaskLayers) || (mode & ApplyToContentLayers) ||
-       (mode & ApplyToNonScrollingContentLayers)) &&
-      mapping->ancestorClippingMaskLayer())
-    f(mapping->ancestorClippingMaskLayer());
 
   if (((mode & ApplyToBackgroundLayer) || (mode & ApplyToContentLayers) ||
        (mode & ApplyToNonScrollingContentLayers)) &&
@@ -2002,7 +1950,7 @@ void CompositedLayerMapping::updateRenderingContext() {
   // Some compositing reasons depend on the compositing state of ancestors. So
   // if we want a rendering context id for the context root, we cannot ask for
   // the id of its associated WebLayer now; it may not have one yet. We could do
-  // a second pass after doing the compositing updates to get these ids, but
+  // a second past after doing the compositing updates to get these ids, but
   // this would actually be harmful. We do not want to attach any semantic
   // meaning to the context id other than the fact that they group a number of
   // layers together for the sake of 3d sorting. So instead we will ask the
@@ -2306,11 +2254,7 @@ static void updateClipParentForGraphicsLayer(
 
 void CompositedLayerMapping::updateClipParent(const PaintLayer* scrollParent) {
   const PaintLayer* clipParent = nullptr;
-  bool haveAncestorClipLayer = false;
-  bool haveAncestorMaskLayer = false;
-  owningLayerClippedOrMaskedByLayerNotAboveCompositedAncestor(
-      scrollParent, haveAncestorClipLayer, haveAncestorMaskLayer);
-  if (!haveAncestorClipLayer) {
+  if (!owningLayerClippedByLayerNotAboveCompositedAncestor(scrollParent)) {
     clipParent = m_owningLayer.clipParent();
     if (clipParent)
       clipParent =
@@ -2850,8 +2794,6 @@ void CompositedLayerMapping::doPaintTask(
   if (!(paintLayerFlags & PaintLayerPaintingOverflowContents)) {
     LayoutRect bounds = paintInfo.compositedBounds;
     bounds.move(paintInfo.paintLayer->subpixelAccumulation());
-    if (paintLayerFlags & PaintLayerPaintingAncestorClippingMaskPhase)
-      bounds.move(offset);
     dirtyRect.intersect(pixelSnappedIntRect(bounds));
   } else {
     dirtyRect.move(
@@ -3129,8 +3071,6 @@ void CompositedLayerMapping::paintContents(
     paintLayerFlags |= PaintLayerPaintingCompositingMaskPhase;
   if (graphicsLayerPaintingPhase & GraphicsLayerPaintChildClippingMask)
     paintLayerFlags |= PaintLayerPaintingChildClippingMaskPhase;
-  if (graphicsLayerPaintingPhase & GraphicsLayerPaintAncestorClippingMask)
-    paintLayerFlags |= PaintLayerPaintingAncestorClippingMaskPhase;
   if (graphicsLayerPaintingPhase & GraphicsLayerPaintOverflowContents)
     paintLayerFlags |= PaintLayerPaintingOverflowContents;
   if (graphicsLayerPaintingPhase & GraphicsLayerPaintCompositedScroll)
@@ -3150,8 +3090,7 @@ void CompositedLayerMapping::paintContents(
       graphicsLayer == m_maskLayer.get() ||
       graphicsLayer == m_childClippingMaskLayer.get() ||
       graphicsLayer == m_scrollingContentsLayer.get() ||
-      graphicsLayer == m_decorationOutlineLayer.get() ||
-      graphicsLayer == m_ancestorClippingMaskLayer.get()) {
+      graphicsLayer == m_decorationOutlineLayer.get()) {
     bool paintRootBackgroundOntoScrollingContentsLayer =
         m_backgroundPaintsOntoScrollingContentsLayer;
     DCHECK(!paintRootBackgroundOntoScrollingContentsLayer ||
@@ -3406,8 +3345,6 @@ String CompositedLayerMapping::debugName(
            ")";
   } else if (graphicsLayer == m_ancestorClippingLayer.get()) {
     name = "Ancestor Clipping Layer";
-  } else if (graphicsLayer == m_ancestorClippingMaskLayer.get()) {
-    name = "Ancestor Clipping Mask Layer";
   } else if (graphicsLayer == m_foregroundLayer.get()) {
     name = m_owningLayer.debugName() + " (foreground) Layer";
   } else if (graphicsLayer == m_backgroundLayer.get()) {