Optimize WebURL -> GURL conversions

Source/weborigin/KURL.h

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2011, 2012 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 61 matching lines @@
     // absolute.
     // FIXME: If the base URL is invalid, this always creates an invalid
     // URL. Instead I think it would be better to treat all invalid base URLs
     // the same way we treate null and empty base URLs.
     KURL(const KURL& base, const String& relative);
     KURL(const KURL& base, const String& relative, const WTF::TextEncoding&);
 
     // For conversions from other structures that have already parsed and
     // canonicalized the URL. The input must be exactly what KURL would have
     // done with the same input.
-    KURL(const CString& canonicalSpec, const url_parse::Parsed&, bool isValid);
+    KURL(const AtomicString& canonicalString, const url_parse::Parsed&, bool isValid);
 
     String strippedForUseAsReferrer() const;
 
     // FIXME: The above functions should be harmonized so that passing a
     // base of null or the empty string gives the same result as the
     // standard String constructor.
 
     // Makes a deep copy. Helpful only if you need to use a KURL on another
     // thread.  Since the underlying StringImpl objects are immutable, there's
     // no other reason to ever prefer copy() over plain old assignment.
@@ skipping 173 matching lines @@
 
 // KURLHash is the default hash for String
 template<typename T> struct DefaultHash;
 template<> struct DefaultHash<WebCore::KURL> {
     typedef WebCore::KURLHash Hash;
 };
 
 } // namespace WTF
 
 #endif // KURL_h