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 b718ca1882a0839b66c99f870912c8c6be51aa7f..6998795659c4d1d2aea0916ab606de89ca5d2c2b 100644
--- a/cc/tiles/picture_layer_tiling.h
+++ b/cc/tiles/picture_layer_tiling.h
@@ -99,6 +99,10 @@ 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 ShouldProcessTileForCheckerImages(const Tile* tile) const;
+
   void set_resolution(TileResolution resolution) {
     resolution_ = resolution;
     may_contain_low_resolution_tiles_ |= resolution == LOW_RESOLUTION;