Added pretty printers for some Ink Drop enums.

ui/views/animation/test/ink_drop_utils.cc

+// Copyright 2016 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 <ostream>
+
+#include "ui/views/animation/ink_drop_animation_ended_reason.h"
+#include "ui/views/animation/ink_drop_hover.h"
+#include "ui/views/animation/ink_drop_state.h"
+
+namespace views {
+
+void PrintTo(InkDropState ink_drop_state, ::std::ostream* os) {
+  *os << ToString(ink_drop_state);
+}
+
+void PrintTo(InkDropHover::AnimationType animation_type, ::std::ostream* os) {
+  *os << ToString(animation_type);
+}
+
+void PrintTo(InkDropAnimationEndedReason reason, ::std::ostream* os) {
+  *os << ToString(reason);
+}
+
+}  // namespace views