Update PaintLayer::needsPaintPhaseXXX flags when add/remove layer on style change

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

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 1234 matching lines @@
         dirtyAncestorChainVisibleDescendantStatus();
 
     if (oldChild->enclosingPaginationLayer())
         oldChild->clearPaginationRecursive();
 
     setNeedsRepaint();
 
     return oldChild;
 }
 
-void PaintLayer::removeOnlyThisLayer()
+void PaintLayer::removeOnlyThisLayerAfterStyleChange()
 {
     if (!m_parent)
         return;
 
+    bool didSetPaintInvalidation = false;
     if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
         DisableCompositingQueryAsserts disabler; // We need the current compositing status.
         if (isPaintInvalidationContainer()) {
             // Our children will be reparented and contained by a new paint invalidation container,
             // so need paint invalidation. CompositingUpdate can't see this layer (which has been
             // removed) so won't do this for us.
             DisablePaintInvalidationStateAsserts disabler;
             layoutObject()->invalidatePaintIncludingNonCompositingDescendants();
             layoutObject()->setShouldDoFullPaintInvalidationIncludingNonCompositingDescendants();
+            didSetPaintInvalidation = true;
         }
     }
 
+    if (!didSetPaintInvalidation && isSelfPaintingLayer()) {
+        if (PaintLayer* enclosingSelfPaintingLayer = m_parent->enclosingSelfPaintingLayer())
+            enclosingSelfPaintingLayer->mergeNeedsPaintPhaseFlagsFrom(*this);
+    }
+
     clipper().clearClipRectsIncludingDescendants();
 
     PaintLayer* nextSib = nextSibling();
 
     // Remove the child reflection layer before moving other child layers.
     // The reflection layer should not be moved to the parent.
     if (PaintLayerReflectionInfo* reflectionInfo = this->reflectionInfo())
         removeChild(reflectionInfo->reflectionLayer());
 
     // Now walk our kids and reattach them to our parent.
     PaintLayer* current = m_first;
     while (current) {
         PaintLayer* next = current->nextSibling();
         removeChild(current);
         m_parent->addChild(current, nextSib);
 
         // FIXME: We should call a specialized version of this function.
         current->updateLayerPositionsAfterLayout();
         current = next;
     }
 
     // Remove us from the parent.
     m_parent->removeChild(this);
     m_layoutObject->destroyLayer();
 }
 
-void PaintLayer::insertOnlyThisLayer()
+void PaintLayer::insertOnlyThisLayerAfterStyleChange()
 {
     if (!m_parent && layoutObject()->parent()) {
         // We need to connect ourselves when our layoutObject() has a parent.
         // Find our enclosingLayer and add ourselves.
         PaintLayer* parentLayer = layoutObject()->parent()->enclosingLayer();
         ASSERT(parentLayer);
         PaintLayer* beforeChild = !parentLayer->reflectionInfo() || parentLayer->reflectionInfo()->reflectionLayer() != this ? layoutObject()->parent()->findNextLayer(parentLayer, layoutObject()) : 0;
         parentLayer->addChild(this, beforeChild);
     }
 
     // Remove all descendant layers from the hierarchy and add them to the new position.
     for (LayoutObject* curr = layoutObject()->slowFirstChild(); curr; curr = curr->nextSibling())
         curr->moveLayers(m_parent, this);
 
+    // If the previous paint invalidation container is not a stacking context and this object is
+    // stacked content, creating this layer may cause this object and its descendants to change
+    // paint invalidation container.
+    bool didSetPaintInvalidation = false;
+    if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled() && !layoutObject()->isLayoutView() && layoutObject()->isRooted() && layoutObject()->styleRef().isStacked()) {
+        const LayoutBoxModelObject& previousPaintInvalidationContainer = layoutObject()->parent()->containerForPaintInvalidation();
+        if (!previousPaintInvalidationContainer.styleRef().isStackingContext()) {
+            layoutObject()->invalidatePaintIncludingNonSelfPaintingLayerDescendants(previousPaintInvalidationContainer);
+            didSetPaintInvalidation = true;
+        }
+    }
+
+    if (!didSetPaintInvalidation && isSelfPaintingLayer()) {
+        if (PaintLayer* enclosingSelfPaintingLayer = m_parent->enclosingSelfPaintingLayer())
+            mergeNeedsPaintPhaseFlagsFrom(*enclosingSelfPaintingLayer);
+    }
+
     // Clear out all the clip rects.
     clipper().clearClipRectsIncludingDescendants();
 }
 
 // Returns the layer reached on the walk up towards the ancestor.
 static inline const PaintLayer* accumulateOffsetTowardsAncestor(const PaintLayer* layer, const PaintLayer* ancestorLayer, LayoutPoint& location)
 {
     ASSERT(ancestorLayer != layer);
 
     const LayoutBoxModelObject* layoutObject = layer->layoutObject();
@@ skipping 1555 matching lines @@
 
 void showLayerTree(const blink::LayoutObject* layoutObject)
 {
     if (!layoutObject) {
         fprintf(stderr, "Cannot showLayerTree. Root is (nil)\n");
         return;
     }
     showLayerTree(layoutObject->enclosingLayer());
 }
 #endif