Report if video capturing meets output protection requirement.

chrome/browser/media/tab_capture_access_handler.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 CHROME_BROWSER_MEDIA_TAB_CAPTURE_ACCESS_HANDLER_H_
 #define CHROME_BROWSER_MEDIA_TAB_CAPTURE_ACCESS_HANDLER_H_
 
 #include "chrome/browser/media/media_access_handler.h"
 
 class MediaStreamCaptureIndicator;
 
 // MediaAccessHandler for TabCapture API.
 class TabCaptureAccessHandler : public MediaAccessHandler {
  public:
   TabCaptureAccessHandler();
   ~TabCaptureAccessHandler() override;
 
   // MediaAccessHandler implementation.
   bool SupportsStreamType(const content::MediaStreamType type,
                           const extensions::Extension* extension) override;
   bool CheckMediaAccessPermission(
       content::WebContents* web_contents,
       const GURL& security_origin,
       content::MediaStreamType type,
       const extensions::Extension* extension) override;
   void HandleRequest(content::WebContents* web_contents,
                      const content::MediaStreamRequest& request,
                      const content::MediaResponseCallback& callback,
                      const extensions::Extension* extension) override;
+  bool IsCaptureInProgress(int render_process_id,
+                           int render_frame_id,
+                           bool* is_link_secure);
+  void UpdateCapturingLinkSecured(int render_process_id,
+                                  int render_frame_id,
+                                  int page_request_id,
+                                  content::MediaStreamType stream_type,
+                                  bool is_secure);
+
+ private:
+  int render_process_id_;

[miu, 2016/04/16 00:05:29]

1. Shouldn't there be a list of render frames and |is_link_secure| state for
each, just like in DesktopCaptureAccessHandler?

2. Instead of duplicating all the "link secure" and "session struct" code here,
consider creating a base class that both DesktopCaptureAccessHandler and
TabCaptureAccessHandler extend from.  For example:

  class CaptureAccessHandlerBase : public MediaAccessHander {
   public:
    bool IsCaptureInProgress(...);
    void UpdateLinkSecured(...);

   private:
    struct Session {
      int render_process_id;
      int render_frame_id;
      int page_request_id;
      bool is_extension_trusted;
      bool is_capturing_link_secure;
    };

    std::list<Session> sessions_;
  };

  class DesktopCaptureAccessHander : public CaptureAccessHandlerBase { ... };
  class TabCaptureAccessHander : public CaptureAccessHandlerBase { ... };

[xjz, 2016/04/21 23:50:45]

Done.

+  int render_frame_id_;
+  bool is_capturing_link_secure_;
+  bool extension_whitelisted_;
 };
 
 #endif  // CHROME_BROWSER_MEDIA_TAB_CAPTURE_ACCESS_HANDLER_H_