Revert of Add CastMediaBlocker and BrowserTest

chromecast/browser/cast_media_blocker.h

-// 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.
-
-#ifndef CHROMECAST_BROWSER_CAST_MEDIA_BLOCKER_H_
-#define CHROMECAST_BROWSER_CAST_MEDIA_BLOCKER_H_
-
-#include "base/macros.h"
-#include "content/public/browser/web_contents_observer.h"
-
-namespace content {
-class WebContents;
-}  // namespace content
-
-namespace chromecast {
-namespace shell {
-
-// This class implements a blocking mode for web applications and is used in
-// Chromecast internal code.
-class CastMediaBlocker : public content::WebContentsObserver {
- public:
-  explicit CastMediaBlocker(content::WebContents* web_contents);
-  ~CastMediaBlocker() override;
-
-  // Sets if the web contents is allowed to play media or not. If media is
-  // unblocked, previously suspended elements should begin playing again.
-  void BlockMediaLoading(bool blocked);
-
- protected:
-  bool media_loading_blocked() const { return state_ == BLOCKED; }
-
-  // Blocks or unblocks the render process from loading new media
-  // according to |media_loading_blocked_|.
-  virtual void UpdateMediaBlockedState();
-
- private:
-  enum BlockState {
-    BLOCKED,     // All media playback should be blocked.
-    UNBLOCKING,  // Media playback should be resumed at next oppurtunity.
-    UNBLOCKED,   // Media playback should not be blocked.
-  };
-
-  // content::WebContentsObserver implementation:
-  void MediaSessionStateChanged(
-      bool is_controllable,
-      bool is_suspended,
-      const base::Optional<content::MediaMetadata>& metadata) override;
-
-  // Whether or not media in the app can be controlled and if media is currently
-  // suspended. These variables cache arguments from MediaSessionStateChanged().
-  bool controllable_;
-  bool suspended_;
-
-  BlockState state_;
-
-  DISALLOW_COPY_AND_ASSIGN(CastMediaBlocker);
-};
-
-}  // namespace shell
-}  // namespace chromecast
-
-#endif  // CHROMECAST_BROWSER_CAST_MEDIA_BLOCKER_H_