cc: Throttle tile priority updates to once a frame.

cc/layer_tree_host_common.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_LAYER_TREE_HOST_COMMON_H_
 #define CC_LAYER_TREE_HOST_COMMON_H_
 
 #include "base/memory/ref_counted.h"
 #include "cc/cc_export.h"
 #include "cc/scoped_ptr_vector.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/transform.h"
 #include "ui/gfx/vector2d.h"
 
 namespace cc {
 
 class LayerImpl;
 class Layer;
 
 class CC_EXPORT LayerTreeHostCommon {
 public:
     static gfx::Rect calculateVisibleRect(const gfx::Rect& targetSurfaceRect, const gfx::Rect& layerBoundRect, const gfx::Transform&);
 
     static void calculateDrawProperties(Layer* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, bool canUseLCDText, std::vector<scoped_refptr<Layer> >& renderSurfaceLayerList);
-    static void calculateDrawProperties(LayerImpl* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, bool canUseLCDText, std::vector<LayerImpl*>& renderSurfaceLayerList);
+    static void calculateDrawProperties(LayerImpl* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, bool canUseLCDText, std::vector<LayerImpl*>& renderSurfaceLayerList, bool updateTilePriorities);
 
     // Performs hit testing for a given renderSurfaceLayerList.
     static LayerImpl* findLayerThatIsHitByPoint(const gfx::PointF& screenSpacePoint, const std::vector<LayerImpl*>& renderSurfaceLayerList);
 
     static LayerImpl* findLayerThatIsHitByPointInTouchHandlerRegion(const gfx::PointF& screenSpacePoint, const std::vector<LayerImpl*>& renderSurfaceLayerList);
 
     static bool layerHasTouchEventHandlersAt(const gfx::PointF& screenSpacePoint, LayerImpl* layerImpl);
 
     template<typename LayerType> static bool renderSurfaceContributesToTarget(LayerType*, int targetSurfaceLayerID);
 
+    template<class Function, typename LayerType> static void callFunctionForSubtree(LayerType* rootLayer);
+
     // Returns a layer with the given id if one exists in the subtree starting
     // from the given root layer (including mask and replica layers).
     template<typename LayerType> static LayerType* findLayerInSubtree(LayerType* rootLayer, int layerId);
 
     static Layer* getChildAsRawPtr(const std::vector<scoped_refptr<Layer> >& children, size_t index)
     {
         return children[index].get();
     }
 
     static LayerImpl* getChildAsRawPtr(const ScopedPtrVector<LayerImpl>& children, size_t index)
@@ skipping 41 matching lines @@
     if (rootLayer->replicaLayer() && rootLayer->replicaLayer()->id() == layerId)
         return rootLayer->replicaLayer();
 
     for (size_t i = 0; i < rootLayer->children().size(); ++i) {
         if (LayerType* found = findLayerInSubtree(getChildAsRawPtr(rootLayer->children(), i), layerId))
             return found;
     }
     return 0;
 }
 
+template<class Function, typename LayerType>
+void LayerTreeHostCommon::callFunctionForSubtree(LayerType* rootLayer)
+{
+    Function()(rootLayer);
+   
+    if (rootLayer->maskLayer())
+        Function()(rootLayer->maskLayer());
+    if (rootLayer->replicaLayer())
+        Function()(rootLayer->replicaLayer());
+
+    for (size_t i = 0; i < rootLayer->children().size(); ++i)
+        callFunctionForSubtree<Function>(getChildAsRawPtr(rootLayer->children(), i));
+}
+
 }  // namespace cc
 
 #endif  // CC_LAYER_TREE_HOST_COMMON_H_