Refactor: Make MediaCaptureDevicesDispatcher have pluggable handlers.

chrome/browser/media/desktop_capture_access_handler.h

Index: chrome/browser/media/desktop_capture_access_handler.h
diff --git a/chrome/browser/media/desktop_capture_access_handler.h b/chrome/browser/media/desktop_capture_access_handler.h
new file mode 100644
index 0000000000000000000000000000000000000000..ac9587691bfa9fa529415bcff241e328dfda469c
--- /dev/null
+++ b/chrome/browser/media/desktop_capture_access_handler.h
@@ -0,0 +1,32 @@
+// Copyright (c) 2015 The Chromium Authors. All rights reserved.

[Sergey Ulanov, 2015/04/24 22:43:51]

nit: Here and in other files: please remove (c)
https://www.chromium.org/developers/coding-style#TOC-File-headers

[changbin, 2015/04/29 05:24:34]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_MEDIA_DESKTOP_CAPTURE_ACCESS_HANDLER_H_
+#define CHROME_BROWSER_MEDIA_DESKTOP_CAPTURE_ACCESS_HANDLER_H_
+
+#include "chrome/browser/media/media_access_handler.h"
+
+class DesktopStreamsRegistry;
+
+class DesktopCaptureAccessHandler : public MediaAccessHandler {
+ public:
+  explicit DesktopCaptureAccessHandler(DesktopStreamsRegistry* registry);
+  ~DesktopCaptureAccessHandler() override;
+
+  void HandleRequest(content::WebContents* web_contents,
+                     const content::MediaStreamRequest& request,
+                     const content::MediaResponseCallback& callback,
+                     const extensions::Extension* extension) override;
+
+ private:
+  void ProcessScreenCaptureAccessRequest(
+      content::WebContents* web_contents,
+      const content::MediaStreamRequest& request,
+      const content::MediaResponseCallback& callback,
+      const extensions::Extension* extension);
+
+  DesktopStreamsRegistry* desktop_streams_registry_;
+};
+
+#endif  // CHROME_BROWSER_MEDIA_DESKTOP_CAPTURE_ACCESS_HANDLER_H_