cc: Rework how picture layer tiling set gets into raster queues.

cc/layers/picture_layer_impl.h

Index: cc/layers/picture_layer_impl.h
diff --git a/cc/layers/picture_layer_impl.h b/cc/layers/picture_layer_impl.h
index e7f4fba7288bb46284b38b7e32d1928267f572d3..2af71788241fc764fbdb2cc7585676bd73706cc0 100644
--- a/cc/layers/picture_layer_impl.h
+++ b/cc/layers/picture_layer_impl.h
@@ -29,15 +29,6 @@ class CC_EXPORT PictureLayerImpl
     : public LayerImpl,
       NON_EXPORTED_BASE(public PictureLayerTilingClient) {
  public:
-  struct CC_EXPORT Pair {
-    Pair();
-    Pair(PictureLayerImpl* active_layer, PictureLayerImpl* pending_layer);
-    ~Pair();
-
-    PictureLayerImpl* active;
-    PictureLayerImpl* pending;
-  };
-
   static scoped_ptr<PictureLayerImpl> Create(
       LayerTreeImpl* tree_impl,
       int id,
@@ -77,6 +68,7 @@ class CC_EXPORT PictureLayerImpl
   TilePriority::PriorityBin GetMaxTilePriorityBin() const override;
   WhichTree GetTree() const override;
   bool RequiresHighResToDraw() const override;
+  bool HasValidTilePriorities() const override;
 
   void UpdateRasterSource(scoped_refptr<RasterSource> raster_source,
                           Region* new_invalidation,
@@ -99,8 +91,6 @@ class CC_EXPORT PictureLayerImpl
   // Functions used by tile manager.
   PictureLayerImpl* GetPendingOrActiveTwinLayer() const;
   bool IsOnActiveOrPendingTree() const;
-  // Virtual for testing.
-  virtual bool HasValidTilePriorities() const;
 
   // Used for benchmarking
   RasterSource* GetRasterSource() const { return raster_source_.get(); }