Make tab capture media stream requests verify that the request came from extension API

chrome/common/extensions/request_media_access_permission_helper.h

Index: chrome/common/extensions/request_media_access_permission_helper.h
diff --git a/chrome/common/extensions/request_media_access_permission_helper.h b/chrome/common/extensions/request_media_access_permission_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..61837cf6b9ba16bb0aff04eeef106a913b3046a5
--- /dev/null
+++ b/chrome/common/extensions/request_media_access_permission_helper.h
@@ -0,0 +1,34 @@
+// Copyright (c) 2012 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_COMMON_EXTENSIONS_REQUEST_MEDIA_ACCESS_PERMISSION_HELPER_H_
+#define CHROME_COMMON_EXTENSIONS_REQUEST_MEDIA_ACCESS_PERMISSION_HELPER_H_
+
+#include "base/callback.h"
+#include "content/public/common/media_stream_request.h"
+
+namespace content{
+typedef base::Callback< void(const MediaStreamDevices&) > MediaResponseCallback;
+}  // namespace content
+
+namespace extensions {
+
+class RequestMediaAccessPermissionHelper {
+ public:
+  static void AuthorizeRequest(const content::MediaStreamRequest* request,
+                               const content::MediaResponseCallback& callback,
+                               bool allow_audio,
+                               bool allow_video,
+                               bool allow_tab_media);
+
+ private:
+  RequestMediaAccessPermissionHelper();
+  ~RequestMediaAccessPermissionHelper();
+
+  DISALLOW_COPY_AND_ASSIGN(RequestMediaAccessPermissionHelper);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_COMMON_EXTENSIONS_REQUEST_MEDIA_ACCESS_PERMISSION_HELPER_H_