Fix CSS reference filters with negative transformed children.

cc/layers/layer.cc

Index: cc/layers/layer.cc
diff --git a/cc/layers/layer.cc b/cc/layers/layer.cc
index 5c0ca54183a4efbe5a6b6f89982113f0bcf71c01..08c5d28f1065341127b96cbd000aecea718e61f2 100644
--- a/cc/layers/layer.cc
+++ b/cc/layers/layer.cc
@@ -477,6 +477,15 @@ void Layer::SetBackgroundFilters(const FilterOperations& filters) {
   SetNeedsCommit();
 }
 
+void Layer::SetFiltersOrigin(const gfx::PointF& filters_origin) {
+  DCHECK(IsPropertyChangeAllowed());
+  if (inputs_.filters_origin == filters_origin)
+    return;
+  inputs_.filters_origin = filters_origin;
+  SetSubtreePropertyChanged();  // TODO(senorblanco) or SetLayerPropertyChanged?

[Stephen White, 2016/08/29 21:10:54]

Ali: any comment on this TODO? I notice that SetFilters() uses
SetSubtreePropertyChanged(), but SetBackgroundFilters() uses
SetLayerPropertyChanged(). Any idea which one I should be using?

[ajuma, 2016/08/29 21:39:30]

It should be SetSubtreePropertyChanged (since the dirty region on screen depends
on the bounds of all descendants). I think the difference for background filters
is that the dirty region depends only on the bounds of the layer itself (and on
the filter).

[Stephen White, 2016/08/29 21:43:11]

Thanks! TODO removed.

+  SetNeedsCommit();
+}
+
 void Layer::SetOpacity(float opacity) {
   DCHECK(IsPropertyChangeAllowed());
   DCHECK_GE(opacity, 0.f);
@@ -1126,6 +1135,7 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
                               layer_tree_host_->source_frame_number();
 
   layer->SetBackgroundColor(inputs_.background_color);
+  layer->SetFiltersOrigin(inputs_.filters_origin);

[ajuma, 2016/08/29 20:28:43]

This shouldn't be needed (since filters_origin will get pushed with the effect
tree).

[Stephen White, 2016/08/29 21:10:54]

Removed.

   layer->SetSafeOpaqueBackgroundColor(safe_opaque_background_color_);
   layer->SetBounds(use_paint_properties ? paint_properties_.bounds
                                         : inputs_.bounds);