[ash-md] Remove the number of animators used for the Shelf animations.

ash/animation/animation_change_type.h

Index: ash/animation/animation_change_type.h
diff --git a/ash/animation/animation_change_type.h b/ash/animation/animation_change_type.h
new file mode 100644
index 0000000000000000000000000000000000000000..99dd63a92b8ba311777e119de5412ee2660a9a34
--- /dev/null
+++ b/ash/animation/animation_change_type.h
@@ -0,0 +1,14 @@
+// Copyright 2017 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.
+
+#ifndef ASH_ANIMATION_ANIMATION_CHANGE_TYPE_H_
+#define ASH_ANIMATION_ANIMATION_CHANGE_TYPE_H_
+
+namespace ash {
+
+enum class AnimationChangeType { ANIMATE, IMMEDIATE };
+
+}  // namespace ash
+
+#endif  // ASH_ANIMATION_ANIMATION_CHANGE_TYPE_H_