cc: Optimize decode scheduling for checker-images.

cc/tiles/picture_layer_tiling.h

Index: cc/tiles/picture_layer_tiling.h
diff --git a/cc/tiles/picture_layer_tiling.h b/cc/tiles/picture_layer_tiling.h
index a74a058c32f2233e6bfd0ea99847e0c4ace7b825..44c4a206cc1303ad44d74387176adc074933a47b 100644
--- a/cc/tiles/picture_layer_tiling.h
+++ b/cc/tiles/picture_layer_tiling.h
@@ -108,6 +108,10 @@ class CC_EXPORT PictureLayerTiling {
   bool IsTileRequiredForActivation(const Tile* tile) const;
   bool IsTileRequiredForDraw(const Tile* tile) const;
 
+  // Returns true if the tile should be processed for decoding images skipped
+  // during rasterization.
+  bool ShouldDecodeCheckeredImagesForTile(const Tile* tile) const;
+
   void set_resolution(TileResolution resolution) {
     resolution_ = resolution;
     may_contain_low_resolution_tiles_ |= resolution == LOW_RESOLUTION;