ui::Layer::SwitchToLayer should finish animations on its old cc::Layer

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index 81e23b49ee7d3c98741125c9e40e627e00e74e48..7a00bbdd7a34e31156a08d107a3c6fad7b8139fa 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -431,6 +431,12 @@ void Layer::SetFillsBoundsOpaquely(bool fills_bounds_opaquely) {
 }
 
 void Layer::SwitchToLayer(scoped_refptr<cc::Layer> new_layer) {
+  // Finish animations being handled by cc_layer_.
+  if (animator_) {
+    animator_->StopAnimatingProperty(LayerAnimationElement::TRANSFORM);
+    animator_->StopAnimatingProperty(LayerAnimationElement::OPACITY);
+  }
+
   if (texture_layer_.get())
     texture_layer_->WillModifyTexture();
   // TODO(piman): delegated_renderer_layer_ cleanup.
@@ -461,6 +467,12 @@ void Layer::SwitchToLayer(scoped_refptr<cc::Layer> new_layer) {
   cc_layer_->SetIsDrawable(IsDrawn());
 }
 
+void Layer::SwitchCCLayerForTest() {
+  scoped_refptr<cc::ContentLayer> new_layer = cc::ContentLayer::Create(this);
+  SwitchToLayer(new_layer);
+  content_layer_ = new_layer;
+}
+
 void Layer::SetExternalTexture(Texture* texture) {
   DCHECK_EQ(type_, LAYER_TEXTURED);
   DCHECK(!solid_color_layer_);