Rename |imp| => |impl| in wtf (one use)

Source/wtf/text/AtomicString.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 32 matching lines @@
     AtomicString(const UChar* s) : m_string(add(s)) { }
 
     template<size_t inlineCapacity>
     explicit AtomicString(const Vector<UChar, inlineCapacity>& characters)
         : m_string(add(characters.data(), characters.size()))
     {
     }
 
     // Constructing an AtomicString from a String / StringImpl can be expensive if
     // the StringImpl is not already atomic.
-    explicit AtomicString(StringImpl* imp) : m_string(add(imp)) { }
+    explicit AtomicString(StringImpl* impl) : m_string(add(impl)) { }
     explicit AtomicString(const String& s) : m_string(add(s.impl())) { }
 
     AtomicString(StringImpl* baseString, unsigned start, unsigned length) : m_string(add(baseString, start, length)) { }
 
     enum ConstructFromLiteralTag { ConstructFromLiteral };
     AtomicString(const char* characters, unsigned length, ConstructFromLiteralTag)
         : m_string(addFromLiteralData(characters, length))
     {
     }
 
@@ skipping 200 matching lines @@
 using WTF::nullAtom;
 using WTF::emptyAtom;
 using WTF::starAtom;
 using WTF::xmlAtom;
 using WTF::xmlnsAtom;
 using WTF::xlinkAtom;
 #endif
 
 #include "wtf/text/StringConcatenate.h"
 #endif // AtomicString_h