Allow multiple WebUIControllerFactory objects to be registered. This makes is possible to implement…

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
===================================================================
--- content/public/browser/content_browser_client.cc	(revision 179096)
+++ content/public/browser/content_browser_client.cc	(working copy)
@@ -26,10 +26,6 @@
   return NULL;
 }
 
-WebUIControllerFactory* ContentBrowserClient::GetWebUIControllerFactory() {
-  return NULL;
-}
-
 GURL ContentBrowserClient::GetEffectiveURL(BrowserContext* browser_context,
                                            const GURL& url) {
   return url;