cc: Do the math for a tile's content rect in layer space once.

cc/layers/picture_layer_impl.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_LAYERS_PICTURE_LAYER_IMPL_H_
 #define CC_LAYERS_PICTURE_LAYER_IMPL_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 37 matching lines @@
   void AppendQuads(RenderPass* render_pass,
                    AppendQuadsData* append_quads_data) override;
   void NotifyTileStateChanged(const Tile* tile) override;
   void DidBeginTracing() override;
   void ReleaseResources() override;
   void RecreateResources() override;
   skia::RefPtr<SkPicture> GetPicture() override;
   Region GetInvalidationRegion() override;
 
   // PictureLayerTilingClient overrides.
-  ScopedTilePtr CreateTile(float contents_scale,
-                           const gfx::Rect& content_rect) override;
+  ScopedTilePtr CreateTile(const Tile::CreateInfo& info) override;
   gfx::Size CalculateTileSize(const gfx::Size& content_bounds) const override;
   const Region* GetPendingInvalidation() override;
   const PictureLayerTiling* GetPendingOrActiveTwinTiling(
       const PictureLayerTiling* tiling) const override;
   bool HasValidTilePriorities() const override;
   bool RequiresHighResToDraw() const override;
   gfx::Rect GetEnclosingRectInTargetSpace() const override;
 
   void set_gpu_raster_max_texture_size(gfx::Size gpu_raster_max_texture_size) {
     gpu_raster_max_texture_size_ = gpu_raster_max_texture_size;
@@ skipping 102 matching lines @@
   // of comparing pointers, since objects pointed to are not guaranteed to
   // exist.
   std::vector<PictureLayerTiling*> last_append_quads_tilings_;
 
   DISALLOW_COPY_AND_ASSIGN(PictureLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_PICTURE_LAYER_IMPL_H_