favor DCHECK_CURRENTLY_ON for better logs in extensions/

extensions/browser/guest_view/web_view/web_view_guest.cc

 // Copyright 2014 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.
 
 #include "extensions/browser/guest_view/web_view/web_view_guest.h"
 
 #include "base/message_loop/message_loop.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/public/browser/browser_context.h"
@@ skipping 146 matching lines @@
     *storage_partition_id = partition_str;
     *persist_storage = false;
   }
 }
 
 void RemoveWebViewEventListenersOnIOThread(
     void* profile,
     const std::string& extension_id,
     int embedder_process_id,
     int view_instance_id) {
-  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
+  DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
   ExtensionWebRequestEventRouter::GetInstance()->RemoveWebViewEventListeners(
       profile,
       extension_id,
       embedder_process_id,
       view_instance_id);
 }
 
 double ConvertZoomLevelToZoomFactor(double zoom_level) {
   double zoom_factor = content::ZoomLevelToZoomFactor(zoom_level);
   // Because the conversion from zoom level to zoom factor isn't perfect, the
@@ skipping 1231 matching lines @@
     scoped_ptr<base::DictionaryValue> args(new base::DictionaryValue());
     DispatchEventToView(
         new GuestViewEvent(webview::kEventExitFullscreen, args.Pass()));
   }
   // Since we changed fullscreen state, sending a Resize message ensures that
   // renderer/ sees the change.
   web_contents()->GetRenderViewHost()->WasResized();
 }
 
 }  // namespace extensions