Revert of Remove about:srcdoc url conversion.

chrome/browser/tracing/navigation_tracing.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_TRACING_NAVIGATION_TRACING_H_
 #define CHROME_BROWSER_TRACING_NAVIGATION_TRACING_H_
 
 #include "base/macros.h"
 #include "content/public/browser/background_tracing_manager.h"
 #include "content/public/browser/web_contents_observer.h"
@@ skipping 13 matching lines @@
   friend class content::WebContentsUserData<NavigationTracingObserver>;
 
   explicit NavigationTracingObserver(content::WebContents* web_contents);
 
   ~NavigationTracingObserver() override;
 
   // content::WebContentsObserver implementation.
   void DidStartProvisionalLoadForFrame(
       content::RenderFrameHost* render_frame_host,
       const GURL& validated_url,
-      bool is_error_page) override;
+      bool is_error_page,
+      bool is_iframe_srcdoc) override;
 
   static content::BackgroundTracingManager::TriggerHandle navigation_handle;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationTracingObserver);
 };
 
 }  // namespace tracing
 
 #endif  // CHROME_BROWSER_TRACING_NAVIGATION_TRACING_H_