Move bit_cast from base/macros.h to its own header

sandbox/win/src/Wow64.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/win/src/Wow64.h"
 
 #include <stddef.h>
 
 #include <sstream>
 
+#include "base/bit_cast.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/win/scoped_process_information.h"
 #include "base/win/windows_version.h"
 #include "sandbox/win/src/target_process.h"
 
 namespace {
 
 // Holds the information needed for the interception of NtMapViewOfSection on
 // 64 bits.
@@ skipping 195 matching lines @@
   SIZE_T read;
   if (!::ReadProcessMemory(child_->Process(), ntdll_, &buffer, kBufferSize,
                            &read))
     return false;
   if (kBufferSize != read)
     return false;
   return true;
 }
 
 }  // namespace sandbox