First Implementation of Snapped Points

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index 1b20f0ebbbd5c18f878365a57d78952df2019a6e..094998163d7eea580c4194b5d93557b426af83b9 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -337,6 +337,7 @@ void LayerImpl::PushPropertiesTo(LayerImpl* layer) {
   layer->SetBounds(bounds_);
   layer->SetScrollClipLayer(scroll_clip_layer_id_);
   layer->SetMutableProperties(mutable_properties_);
+  layer->SetScrollSnapOffsets(snap_offsets_);
 
   // If the main thread commits multiple times before the impl thread actually
   // draws, then damage tracking will become incorrect if we simply clobber the
@@ -506,6 +507,13 @@ void LayerImpl::SetBounds(const gfx::Size& bounds) {
   NoteLayerPropertyChanged();
 }
 
+void LayerImpl::SetScrollSnapOffsets(const SnapPointList& offsets) {
+  snap_offsets_ = offsets;
+  layer_tree_impl()->DidUpdateScrollState(id());
+
+  NoteLayerPropertyChanged();
+}
+
 void LayerImpl::SetViewportBoundsDelta(const gfx::Vector2dF& bounds_delta) {
   DCHECK(IsActive());