Add AndroidVideoSurfaceChooser to manage overlays.

media/base/android/mock_android_overlay.cc

Index: media/base/android/mock_android_overlay.cc
diff --git a/media/base/android/mock_android_overlay.cc b/media/base/android/mock_android_overlay.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9ce74923d3fbe6f86df04b34e3a4d250085d57ce
--- /dev/null
+++ b/media/base/android/mock_android_overlay.cc
@@ -0,0 +1,28 @@
+// 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.
+
+#include "media/base/android/mock_android_overlay.h"
+
+namespace media {
+
+MockAndroidOverlay::MockAndroidOverlay() : weak_factory_(this) {}
+MockAndroidOverlay::~MockAndroidOverlay() {}
+
+void MockAndroidOverlay::SetConfig(const Config& config) {
+  config_ = config;
+}
+
+void MockAndroidOverlay::OnOverlayReady() {
+  config_.ready_cb.Run(this);
+}
+
+void MockAndroidOverlay::OnOverlayFailed() {
+  config_.failed_cb.Run(this);
+}
+
+void MockAndroidOverlay::OnSurfaceDestroyed() {
+  config_.destroyed_cb.Run(this);
+}
+
+}  // namespace media