cc: Remove the base RasterSource

cc/tiles/picture_layer_tiling_set.h

Index: cc/tiles/picture_layer_tiling_set.h
diff --git a/cc/tiles/picture_layer_tiling_set.h b/cc/tiles/picture_layer_tiling_set.h
index b3e22fe34af4b3442d2f1c935a2fa7a06d6254c6..c6d3589d333e011e57913e6fed39b086d822afbc 100644
--- a/cc/tiles/picture_layer_tiling_set.h
+++ b/cc/tiles/picture_layer_tiling_set.h
@@ -56,7 +56,7 @@ class CC_EXPORT PictureLayerTilingSet {
 
   // This function is called on the active tree during activation.
   void UpdateTilingsToCurrentRasterSourceForActivation(
-      scoped_refptr<RasterSource> raster_source,
+      scoped_refptr<DisplayListRasterSource> raster_source,
       const PictureLayerTilingSet* pending_twin_set,
       const Region& layer_invalidation,
       float minimum_contents_scale,
@@ -64,18 +64,19 @@ class CC_EXPORT PictureLayerTilingSet {
 
   // This function is called on the sync tree during commit.
   void UpdateTilingsToCurrentRasterSourceForCommit(
-      scoped_refptr<RasterSource> raster_source,
+      scoped_refptr<DisplayListRasterSource> raster_source,
       const Region& layer_invalidation,
       float minimum_contents_scale,
       float maximum_contents_scale);
 
   // This function is called on the sync tree right after commit.
   void UpdateRasterSourceDueToLCDChange(
-      const scoped_refptr<RasterSource>& raster_source,
+      const scoped_refptr<DisplayListRasterSource>& raster_source,
       const Region& layer_invalidation);
 
-  PictureLayerTiling* AddTiling(float contents_scale,
-                                scoped_refptr<RasterSource> raster_source);
+  PictureLayerTiling* AddTiling(
+      float contents_scale,
+      scoped_refptr<DisplayListRasterSource> raster_source);
   size_t num_tilings() const { return tilings_.size(); }
   int NumHighResTilings() const;
   PictureLayerTiling* tiling_at(size_t idx) { return tilings_[idx]; }
@@ -180,7 +181,7 @@ class CC_EXPORT PictureLayerTilingSet {
 
   void CopyTilingsAndPropertiesFromPendingTwin(
       const PictureLayerTilingSet* pending_twin_set,
-      const scoped_refptr<RasterSource>& raster_source,
+      const scoped_refptr<DisplayListRasterSource>& raster_source,
       const Region& layer_invalidation);
 
   // Remove one tiling.