[mus+ash] Implements hit-test client in Aura

components/viz/client/hit_test_data_provider.h

+// 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 COMPONENTS_VIZ_CLIENT_HIT_TEST_DATA_PROVIDER_H_
+#define COMPONENTS_VIZ_CLIENT_HIT_TEST_DATA_PROVIDER_H_
+
+#include <memory>
+#include <vector>
+
+#include "base/macros.h"
+#include "components/viz/common/display_hit_test_region.h"
+
+namespace viz {
+
+class HitTestDataProvider {
+ public:
+  using HitTestRegionList = std::vector<DisplayHitTestRegion>;
+
+  HitTestDataProvider() = default;
+  virtual ~HitTestDataProvider() = default;
+
+  // Returns an array of hit-test regions.
+  virtual std::unique_ptr<HitTestRegionList> GetHitTestData() = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(HitTestDataProvider);
+};
+
+}  // namespace viz
+
+#endif  // COMPONENTS_VIZ_CLIENT_HIT_TEST_DATA_PROVIDER_H_