Delete chicken/egg compositing geometry updates

After this CL, we don't update the graphics layer geometry incrementally.
Instead, the updates are deferred until its actually time to do a compositing
update. There's a lot of cleanup we can do after this CL lands, but I wanted to
keep this CL small. We can do the cleanup in subsequent CLs.

Review URL: https://codereview.chromium.org/218993017

git-svn-id: svn://svn.chromium.org/blink/trunk@170630 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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

@@ -430,27 +430,6 @@ void CompositedLayerMapping::updateCompositingReasons()
 
 void CompositedLayerMapping::updateAfterLayout(bool needsFullRepaint, bool isUpdateRoot)
 {
-    RenderLayerCompositor* layerCompositor = compositor();
-    if (!layerCompositor->compositingLayersNeedRebuild()) {
-        // Calling updateGraphicsLayerGeometry() here gives incorrect results, because the
-        // position of this layer's GraphicsLayer depends on the position of our compositing
-        // ancestor's GraphicsLayer. That cannot be determined until all the descendant
-        // RenderLayers of that ancestor have been processed via updateLayerPositions().
-        //
-        // The solution is to update compositing children of this layer here,
-        // via updateCompositingChildrenGeometry().
-        updateCompositedBounds(GraphicsLayerUpdater::ForceUpdate);
-        layerCompositor->updateCompositingDescendantGeometry(m_owningLayer.stackingNode(), &m_owningLayer);
-
-        if (isUpdateRoot) {
-            updateGraphicsLayerGeometry(GraphicsLayerUpdater::ForceUpdate);
-            layerCompositor->updateRootLayerPosition();
-            RenderLayerStackingNode* stackingContainer = m_owningLayer.stackingNode()->enclosingStackingContainerNode();
-            if (!layerCompositor->compositingLayersNeedRebuild() && stackingContainer && (stackingContainer != m_owningLayer.stackingNode()))
-                layerCompositor->updateCompositingDescendantGeometry(stackingContainer, stackingContainer->layer());
-        }
-    }
-
     if (needsFullRepaint && !paintsIntoCompositedAncestor())
         setContentsNeedDisplay();
 }

third_party/WebKit/Source/core/rendering/compositing/RenderLayerCompositor.cpp

@@ -372,6 +372,7 @@ void RenderLayerCompositor::setNeedsCompositingUpdate(CompositingUpdateType upda
         break;
     case CompositingUpdateAfterLayout:
         m_needsToRecomputeCompositingRequirements = true;
+        m_needsToUpdateLayerTreeGeometry = true;
         break;
     case CompositingUpdateOnScroll:
         m_needsToRecomputeCompositingRequirements = true; // Overlap can change with scrolling, so need to check for hierarchy updates.
@@ -1406,40 +1407,6 @@ bool RenderLayerCompositor::parentFrameContentLayers(RenderPart* renderer)
     return true;
 }
 
-// Recurs down the RenderLayer tree until its finds the compositing descendants of compositingAncestor and updates their geometry.
-void RenderLayerCompositor::updateCompositingDescendantGeometry(RenderLayerStackingNode* compositingAncestor, RenderLayer* layer)
-{
-    if (layer->stackingNode() != compositingAncestor) {
-        if (layer->hasCompositedLayerMapping()) {
-            CompositedLayerMappingPtr compositedLayerMapping = layer->compositedLayerMapping();
-            compositedLayerMapping->updateCompositedBounds(GraphicsLayerUpdater::ForceUpdate);
-
-            if (layer->reflectionInfo()) {
-                RenderLayer* reflectionLayer = layer->reflectionInfo()->reflectionLayer();
-                if (reflectionLayer->hasCompositedLayerMapping())
-                    reflectionLayer->compositedLayerMapping()->updateCompositedBounds(GraphicsLayerUpdater::ForceUpdate);
-            }
-
-            compositedLayerMapping->updateGraphicsLayerGeometry(GraphicsLayerUpdater::ForceUpdate);
-            return;
-        }
-    }
-
-    if (layer->reflectionInfo())
-        updateCompositingDescendantGeometry(compositingAncestor, layer->reflectionInfo()->reflectionLayer());
-
-    if (!layer->hasCompositingDescendant())
-        return;
-
-#if !ASSERT_DISABLED
-    LayerListMutationDetector mutationChecker(layer->stackingNode());
-#endif
-
-    RenderLayerStackingNodeIterator iterator(*layer->stackingNode(), AllChildren);
-    while (RenderLayerStackingNode* curNode = iterator.next())
-        updateCompositingDescendantGeometry(compositingAncestor, curNode->layer());
-}
-
 void RenderLayerCompositor::repaintCompositedLayers()
 {
     recursiveRepaintLayer(rootRenderLayer());

third_party/WebKit/Source/core/rendering/compositing/RenderLayerCompositor.h

@@ -112,9 +112,6 @@ public:
     // (At the moment, it also has some legacy compatibility hacks.)
     void updateLayerCompositingState(RenderLayer*, UpdateLayerCompositingStateOptions = Normal);
 
-    // Update the geometry for compositing children of compositingAncestor.
-    void updateCompositingDescendantGeometry(RenderLayerStackingNode* compositingAncestor, RenderLayer*);
-
     // Whether layer's compositedLayerMapping needs a GraphicsLayer to do clipping by an ancestor (non-stacking-context parent with overflow).
     bool clippedByAncestor(const RenderLayer*) const;
     // Whether layer's compositedLayerMapping needs a GraphicsLayer to clip z-order children of the given RenderLayer.