Implemented prototype for new ink drop specs.

ui/views/animation/test/test_ink_drop_host.h

+// Copyright 2015 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 UI_VIEWS_ANIMATION_TEST_TEST_INK_DROP_HOST_H_
+#define UI_VIEWS_ANIMATION_TEST_TEST_INK_DROP_HOST_H_
+
+#include "base/macros.h"
+#include "ui/views/animation/ink_drop_host.h"
+
+namespace views {
+
+// A non-functional, dummy implementation of an InkDropHost that can be used as
+// a placeholder during tests.
+class TestInkDropHost : public InkDropHost {
+ public:
+  TestInkDropHost();
+  ~TestInkDropHost() override;
+
+  // TestInkDropHost:
+  void AddInkDropLayer(ui::Layer* ink_drop_layer) override;
+  void RemoveInkDropLayer(ui::Layer* ink_drop_layer) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestInkDropHost);
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_ANIMATION_TEST_TEST_INK_DROP_HOST_H_