compositor-worker: cc->blink mutation plumbing

content/renderer/gpu/render_widget_compositor.cc

Index: content/renderer/gpu/render_widget_compositor.cc
diff --git a/content/renderer/gpu/render_widget_compositor.cc b/content/renderer/gpu/render_widget_compositor.cc
index beaae7530bfa6fb3aab4c34729915d5fcb5c4f78..d7b581a724053f09b9fcf618873736661157eb02 100644
--- a/content/renderer/gpu/render_widget_compositor.cc
+++ b/content/renderer/gpu/render_widget_compositor.cc
@@ -906,6 +906,11 @@ void RenderWidgetCompositor::ApplyViewportDeltas(
                                  top_controls_delta);
 }
 
+void RenderWidgetCompositor::ApplyMutations(
+    const cc::LayerTreeMutations& mutations) {
+  delegate_->ApplyMutations(mutations);
+}
+
 void RenderWidgetCompositor::RequestNewOutputSurface() {
   // If the host is closing, then no more compositing is possible.  This
   // prevents shutdown races between handling the close message and