Thread ui opacity animations

cc/animation_id_provider.cc

Index: cc/animation_id_provider.cc
diff --git a/cc/animation_id_provider.cc b/cc/animation_id_provider.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bf302837b40679b95e9236694d632827a413288e
--- /dev/null
+++ b/cc/animation_id_provider.cc
@@ -0,0 +1,19 @@
+// Copyright (c) 2013 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 "cc/animation_id_provider.h"
+
+namespace cc {
+
+int AnimationIdProvider::NextAnimationId() {
+  static int next_animation_id = 1;
+  return next_animation_id++;
+}
+
+int AnimationIdProvider::NextGroupId() {
+  static int next_group_id = 1;
+  return next_group_id++;
+}
+
+}  // namespace cc