Add support for converting cc::FilterOperations into an SkImageFilter

cc/trees/occlusion_tracker.cc

Index: cc/trees/occlusion_tracker.cc
diff --git a/cc/trees/occlusion_tracker.cc b/cc/trees/occlusion_tracker.cc
index 9fc26da566700ce9b46cb88974730ba722a6b155..abaefa775282502f6c853e7b39bc80f687d25a85 100644
--- a/cc/trees/occlusion_tracker.cc
+++ b/cc/trees/occlusion_tracker.cc
@@ -233,14 +233,11 @@ void OcclusionTrackerBase<LayerType, RenderSurfaceType>::FinishedRenderTarget(
 
   // If the occlusion within the surface can not be applied to things outside of
   // the surface's subtree, then clear the occlusion here so it won't be used.
-  // TODO(senorblanco):  Make this smarter for SkImageFilter case:  once
-  // SkImageFilters can report affectsOpacity(), call that.
   if (finished_target->mask_layer() ||
       !SurfaceOpacityKnown(surface) ||
       surface->draw_opacity() < 1 ||
       target_is_only_for_copy_request ||
-      finished_target->filters().HasFilterThatAffectsOpacity() ||
-      finished_target->filter()) {
+      finished_target->filters().HasFilterThatAffectsOpacity()) {
     stack_.back().occlusion_from_outside_target.Clear();
     stack_.back().occlusion_from_inside_target.Clear();
   } else if (!SurfaceTransformsToTargetKnown(surface)) {