[animations] Adds metrics for jank on selected layer animations

ui/compositor/test/test_layer_animation_delegate.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/compositor/layer.h"
 #include "ui/compositor/test/test_layer_animation_delegate.h"
 
 namespace ui {
 
 TestLayerThreadedAnimationDelegate::TestLayerThreadedAnimationDelegate() {}
@@ skipping 97 matching lines @@
 
 cc::Layer* TestLayerAnimationDelegate::GetCcLayer() const {
   return cc_layer_.get();
 }
 
 LayerThreadedAnimationDelegate*
 TestLayerAnimationDelegate::GetThreadedAnimationDelegate() {
   return &threaded_delegate_;
 }
 
+int TestLayerAnimationDelegate::GetFrameNumber() {
+  return 0;
+}
+
 void TestLayerAnimationDelegate::CreateCcLayer() {
   cc_layer_ = cc::Layer::Create();
 }
 
 void TestLayerThreadedAnimationDelegate::AddThreadedAnimation(
     std::unique_ptr<cc::Animation> animation) {}
 
 void TestLayerThreadedAnimationDelegate::RemoveThreadedAnimation(
     int animation_id) {}
 
 }  // namespace ui