Added activity logging for ext APIs with custom bindings

chrome/renderer/extensions/dom_activity_logger.h

 // Copyright (c) 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.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_DOM_ACTIVITY_LOGGER_H_
 #define CHROME_RENDERER_EXTENSIONS_DOM_ACTIVITY_LOGGER_H_
 
 #include <string>
 
 #include "base/string_piece.h"
 #include "googleurl/src/gurl.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebString.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDOMActivityLogger.h"
 #include "v8/include/v8.h"
 
 using WebKit::WebString;
 
+// Used to log DOM API calls from within WebKit. The events are sent via IPC to
+// extensions::ActivityLog for recording and display.
 namespace extensions {
 
 class DOMActivityLogger: public WebKit::WebDOMActivityLogger {
  public:
   static const int kMainWorldId = 0;
   DOMActivityLogger(const std::string& extension_id,
                     const GURL& url,
                     const string16& title);
 
   // Marshalls the arguments into an ExtensionHostMsg_DOMAction_Params
@@ skipping 19 matching lines @@
   GURL url_;
   string16 title_;
 
   DISALLOW_COPY_AND_ASSIGN(DOMActivityLogger);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_DOM_ACTIVITY_LOGGER_H_