cc: Remove low quality mode and cleanup tile versions.

cc/resources/picture_layer_tiling.h

Index: cc/resources/picture_layer_tiling.h
diff --git a/cc/resources/picture_layer_tiling.h b/cc/resources/picture_layer_tiling.h
index 104ca107753e3ef12fb34f6fca6361d18231309d..2d0ae37c66800fadb7bb1968220d7406cf6b2fd1 100644
--- a/cc/resources/picture_layer_tiling.h
+++ b/cc/resources/picture_layer_tiling.h
@@ -101,8 +101,7 @@ class CC_EXPORT PictureLayerTiling {
 
     void AdvancePhase();
     bool TileNeedsRaster(Tile* tile) const {
-      RasterMode mode = tile->DetermineRasterModeForTree(tree_);
-      return !tile->is_occluded(tree_) && tile->NeedsRasterForMode(mode);
+      return !tile->is_occluded(tree_) && !tile->IsReadyToDraw();
     }
 
     PictureLayerTiling* tiling_;