Add WebRTC logging extension API.

chrome/common/extensions/api/webrtc_logging_private.idl

+// Copyright 2013 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.
+
+// Use the <code>chrome.webrtcLoggingPrivate</code> API to control diagnostic
+// WebRTC logging.
+[nodoc] namespace webrtcLoggingPrivate {
+  interface Functions {
+    // Starts logging. If logging has already been started for this render
+    // process, the call will be ignored. |appSessionId| is the unique session
+    // ID which will be added to the log.
+    static void start(DOMString appSessionId);
+
+    // Sets whether the log should be uploaded automatically for the case when
+    // the render process goes away (tab is closed or crashes) and stop has not
+    // been called before that. If |shouldUpload| is true it will be uploaded,
+    // otherwise it will be discarded. The default setting is to discard it.
+    static void setUploadOnRenderClose(boolean shouldUpload);
+
+    // Stops logging and, if |upload| is true, uploads the log. If |upload| is
+    // false the log is discarded.
+    static void stop(boolean upload);
+  };
+};