Remove the url parameter from blink::Platform::userAgent since it's not used anymore.

public/platform/Platform.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 305 matching lines @@
 
     // May return null.
     virtual WebPrescientNetworking* prescientNetworking() { return 0; }
 
     // Returns a new WebSocketStreamHandle instance.
     virtual WebSocketStreamHandle* createSocketStreamHandle() { return 0; }
 
     // Returns a new WebSocketHandle instance.
     virtual WebSocketHandle* createWebSocketHandle() { return 0; }
 
-    // Returns the User-Agent string that should be used for the given URL.
-    virtual WebString userAgent(const WebURL&) { return WebString(); }
+    // Returns the User-Agent string.
+    virtual WebString userAgent() { return WebString(); }
 
     // A suggestion to cache this metadata in association with this URL.
     virtual void cacheMetadata(const WebURL&, double responseTime, const char* data, size_t dataSize) { }
 
     // Returns the decoded data url if url had a supported mimetype and parsing was successful.
     virtual WebData parseDataURL(const WebURL&, WebString& mimetype, WebString& charset) { return WebData(); }
 
     virtual WebURLError cancelledError(const WebURL&) const { return WebURLError(); }
 
 
@@ skipping 301 matching lines @@
     virtual WebDatabaseObserver* databaseObserver() { return 0; }
 
 
 protected:
     virtual ~Platform() { }
 };
 
 } // namespace blink
 
 #endif