cc: Early out of UpdateTiles for resoureceless draw

cc/layers/picture_layer_impl.h

Index: cc/layers/picture_layer_impl.h
diff --git a/cc/layers/picture_layer_impl.h b/cc/layers/picture_layer_impl.h
index 8a2465a15bc380c240027b54323e4757fb50f998..03316dcd011b39dcfee78187d45dc73035c2c2a7 100644
--- a/cc/layers/picture_layer_impl.h
+++ b/cc/layers/picture_layer_impl.h
@@ -71,7 +71,7 @@ class CC_EXPORT PictureLayerImpl
   void UpdateRasterSource(scoped_refptr<DisplayListRasterSource> raster_source,
                           Region* new_invalidation,
                           const PictureLayerTilingSet* pending_set);
-  bool UpdateTiles(bool resourceless_software_draw);
+  bool UpdateTiles();
   void UpdateCanUseLCDTextAfterCommit();
   bool RasterSourceUsesLCDText() const;
   WhichTree GetTree() const;
@@ -156,15 +156,9 @@ class CC_EXPORT PictureLayerImpl
 
   bool nearest_neighbor_;
 
-  // Any draw properties derived from |transform|, |viewport|, and |clip|
-  // parameters in LayerTreeHostImpl::OnDraw are not valid for prioritizing
-  // tiles during resourceless software draws. This is because resourceless
-  // software draws can have wildly different transforms/viewports from regular
-  // draws. Save a copy of the required draw properties of the last frame that
-  // has a valid viewport for prioritizing tiles.
-  gfx::Rect visible_rect_for_tile_priority_;
+  // Use this instead of |visible_layer_rect()| for tiling calculations. This
+  // takes external viewport and transform for tile priority into account.
   gfx::Rect viewport_rect_for_tile_priority_in_content_space_;
-  gfx::Transform screen_space_transform_for_tile_priority_;
 
   gfx::Size gpu_raster_max_texture_size_;