Provide a std::vector compliant empty() method for WebVector.

third_party/WebKit/public/platform/WebVector.h

 /*
  * Copyright (C) 2009 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 93 matching lines @@
   void assign(const C& other) {
     m_data.assign(other.begin(), other.end());
   }
 
   template <typename U>
   void assign(const U* values, size_t size) {
     m_data.assign(values, values + size);
   }
 
   size_t size() const { return m_data.size(); }
-  bool isEmpty() const { return m_data.empty(); }
+  bool empty() const { return m_data.empty(); }
+  // TODO(slangley): Remove all uses of isEmpty.
+  bool isEmpty() const { return empty(); }
 
   T& operator[](size_t i) {
     DCHECK_LT(i, m_data.size());
     return m_data[i];
   }
 
   const T& operator[](size_t i) const {
     DCHECK_LT(i, m_data.size());
     return m_data[i];
   }
 
   T* data() { return m_data.data(); }
   const T* data() const { return m_data.data(); }
 
   iterator begin() { return m_data.begin(); }
   iterator end() { return m_data.end(); }
   const_iterator begin() const { return m_data.begin(); }
   const_iterator end() const { return m_data.end(); }
 
   void swap(WebVector<T>& other) { m_data.swap(other.m_data); }
 
  private:
   std::vector<T> m_data;
 };
 
 }  // namespace blink
 
 #endif