cc: nine patch: add occlusion support

cc/layers/nine_patch_layer.cc

Index: cc/layers/nine_patch_layer.cc
diff --git a/cc/layers/nine_patch_layer.cc b/cc/layers/nine_patch_layer.cc
index e2dc92f344e5ccc40daa01d967e11524f0ae731f..c78345bc055a207c1b625d5e25638ab4e0a9187d 100644
--- a/cc/layers/nine_patch_layer.cc
+++ b/cc/layers/nine_patch_layer.cc
@@ -57,6 +57,14 @@ void NinePatchLayer::SetNearestNeighbor(bool nearest_neighbor) {
   SetNeedsCommit();
 }
 
+void NinePatchLayer::SetLayerOcclusion(const gfx::Rect& rect) {
+  if (layer_occlusion_ == rect)
+    return;
+
+  layer_occlusion_ = rect;
+  SetNeedsCommit();
+}
+
 void NinePatchLayer::PushPropertiesTo(LayerImpl* layer) {
   UIResourceLayer::PushPropertiesTo(layer);
   TRACE_EVENT0("cc", "NinePatchLayer::PushPropertiesTo");
@@ -68,7 +76,7 @@ void NinePatchLayer::PushPropertiesTo(LayerImpl* layer) {
     DCHECK(layer_tree_host());
 
     layer_impl->SetLayout(image_aperture_, border_, fill_center_,
-                          nearest_neighbor_);
+                          nearest_neighbor_, layer_occlusion_);
   }
 }