cc: Stop pushing properties every activation for picture layers.

cc/resources/picture_layer_tiling.h

 // Copyright 2012 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_RESOURCES_PICTURE_LAYER_TILING_H_
 #define CC_RESOURCES_PICTURE_LAYER_TILING_H_
 
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 15 matching lines @@
 }
 }
 
 namespace cc {
 
 class PictureLayerTiling;
 class RasterSource;
 
 class CC_EXPORT PictureLayerTilingClient {
  public:
+  // Callback to notify the client that the PictureLayerTilingSet changed (ie. a
+  // tiling was added or removed).

[vmpstr, 2015/01/23 20:57:58]

From the patch you have, this doesn't include any type of priority/rect changes,
should it?

[danakj, 2015/01/23 21:11:36]

I don't think so.. live rect changes would come with a new rastersource if
they're changes from the pending tree.

The pending tree only has a single tiling, so it doesn't just change tiling
priority, it would remove/add a tiling.

+  virtual void TilingSetChanged() = 0;
+
   // Create a tile at the given content_rect (in the contents scale of the
   // tiling) This might return null if the client cannot create such a tile.
   virtual scoped_refptr<Tile> CreateTile(float contents_scale,
                                          const gfx::Rect& content_rect) = 0;
   virtual gfx::Size CalculateTileSize(
     const gfx::Size& content_bounds) const = 0;
   // This invalidation region defines the area (if any, it can by null) that
   // tiles can not be shared between pending and active trees.
   virtual const Region* GetPendingInvalidation() = 0;
   virtual const PictureLayerTiling* GetPendingOrActiveTwinTiling(
@@ skipping 271 matching lines @@
 
  private:
   DISALLOW_ASSIGN(PictureLayerTiling);
 
   RectExpansionCache expansion_cache_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_LAYER_TILING_H_