Add flag for enabling/disabling video fullscreen detection

chrome/browser/android/app_hooks.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 CHROME_BROWSER_ANDROID_APP_HOOKS_H_
+#define CHROME_BROWSER_ANDROID_APP_HOOKS_H_
+
+#include <jni.h>
+#include "base/macros.h"
+
+namespace chrome {
+namespace android {
+
+class AppHooks {
+ public:
+  static bool ShouldDetectVideoFullscreen();
+
+ private:
+  AppHooks();
+  ~AppHooks();
+
+  DISALLOW_COPY_AND_ASSIGN(AppHooks);
+};
+
+}  // namespace android
+}  // namespace chrome
+
+#endif  // CHROME_BROWSER_ANDROID_APP_HOOKS_H_