cc: Do solid color analysis before scheduling tiles.

cc/tiles/tile.h

Index: cc/tiles/tile.h
diff --git a/cc/tiles/tile.h b/cc/tiles/tile.h
index 6ca9e87e21c32a761618247f8a1293054ab2916b..99497f3ad20a3c0d0eee59b18a2c3b33e251e09d 100644
--- a/cc/tiles/tile.h
+++ b/cc/tiles/tile.h
@@ -104,6 +104,8 @@ class CC_EXPORT Tile {
     return invalidated_content_rect_;
   }
 
+  bool HasRasterTask() const { return !!raster_task_.get(); }
+
  private:
   friend class TileManager;
   friend class FakeTileManager;
@@ -117,8 +119,6 @@ class CC_EXPORT Tile {
        int flags);
   ~Tile();
 
-  bool HasRasterTask() const { return !!raster_task_.get(); }
-
   TileManager* const tile_manager_;
   const gfx::Rect content_rect_;
   const gfx::Rect enclosing_layer_rect_;