CC Animations: Make LayerAnimationController creation optional

cc/blink/web_layer_impl.h

Index: cc/blink/web_layer_impl.h
diff --git a/cc/blink/web_layer_impl.h b/cc/blink/web_layer_impl.h
index beaf3b51679ab34a60520a79c3fac724c0e18a53..c60df91cedda933260fe27d1122e44646863fd7d 100644
--- a/cc/blink/web_layer_impl.h
+++ b/cc/blink/web_layer_impl.h
@@ -39,6 +39,7 @@ class ConvertableToTraceFormat;
 
 namespace cc {
 class Layer;
+class LayerSettings;
 }
 
 namespace cc_blink {
@@ -54,6 +55,10 @@ class WebLayerImpl : public blink::WebLayer, public cc::LayerClient {
   static bool UsingPictureLayer();
   CC_BLINK_EXPORT static void SetImplSidePaintingEnabled(bool enabled);
 
+  CC_BLINK_EXPORT static void SetLayerSettings(
+      const cc::LayerSettings& settings);
+  CC_BLINK_EXPORT static cc::LayerSettings& LayerSettings();
+
   CC_BLINK_EXPORT cc::Layer* layer() const;
 
   // WebLayer implementation.