Remove redundant branch and add an UNLIKELY.

Source/wtf/Vector.h

 /*
  *  Copyright (C) 2005, 2006, 2007, 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 817 matching lines @@
         ASSERT(size >= m_size);
         if (size > capacity())
             expandCapacity(size);
         TypeOperations::initialize(end(), begin() + size);
         m_size = size;
     }
 
     template<typename T, size_t inlineCapacity>
     void Vector<T, inlineCapacity>::reserveCapacity(size_t newCapacity)
     {
-        if (newCapacity <= capacity())
+        if (UNLIKELY(newCapacity <= capacity()))
             return;
         T* oldBuffer = begin();
         T* oldEnd = end();
         Base::allocateBuffer(newCapacity);
-        if (begin())
-            TypeOperations::move(oldBuffer, oldEnd, begin());
+        TypeOperations::move(oldBuffer, oldEnd, begin());
         Base::deallocateBuffer(oldBuffer);
     }
 
     template<typename T, size_t inlineCapacity>
     inline void Vector<T, inlineCapacity>::reserveInitialCapacity(size_t initialCapacity)
     {
         ASSERT(!m_size);
         ASSERT(capacity() == inlineCapacity);
         if (initialCapacity > inlineCapacity)
             Base::allocateBuffer(initialCapacity);
@@ skipping 209 matching lines @@
     inline bool operator!=(const Vector<T, inlineCapacity>& a, const Vector<T, inlineCapacity>& b)
     {
         return !(a == b);
     }
 
 } // namespace WTF
 
 using WTF::Vector;
 
 #endif // WTF_Vector_h