Report if video capturing meets output protection requirement.

media/base/video_capturer_source.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 MEDIA_BASE_VIDEO_CAPTURER_SOURCE_H_
 #define MEDIA_BASE_VIDEO_CAPTURER_SOURCE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 68 matching lines @@
   // Asks source to send a refresh frame. In cases where source does not provide
   // a continuous rate of new frames (e.g. canvas capture, screen capture where
   // the screen's content has not changed in a while), consumers may request a
   // "refresh frame" to be delivered. For instance, this would be needed when
   // a new sink is added to a MediaStreamTrack.
   // The default implementation is a no-op and implementations are not required
   // to honor this request. If they decide to and capturing is started
   // successfully, then |new_frame_callback| should be called with a frame.
   virtual void RequestRefreshFrame() {}
 
+  // Notifies source the capturing link is secure. This is required by content
+  // output protection.
+  virtual void SetCapturingLinkSecured(bool is_secure) {}

[miu, 2016/04/26 01:25:14]

Do we need this in the interface definition?  It seems like this is side-detail
that only applies to the MediaStream framework in libcontent (and src/chrome
code).

[xjz, 2016/04/29 00:11:42]

Done. Removed the definition.

+
   // Stops capturing frames and clears all callbacks including the
   // SupportedFormatsCallback callback. Note that queued frame callbacks
   // may still occur after this call, so the caller must take care to
   // use refcounted or weak references in |new_frame_callback|.
   virtual void StopCapture() = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_CAPTURER_SOURCE_H_