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

chrome/browser/profile_resetter/triggered_profile_resetter_win_unittest.cc

 // Copyright 2015 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 "chrome/browser/profile_resetter/triggered_profile_resetter.h"
 
 #include <stdint.h>
 
+#include "base/bit_cast.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/field_trial.h"
 #include "base/prefs/pref_service.h"
 #include "base/test/test_reg_util_win.h"
 #include "base/win/registry.h"
 #include "chrome/browser/prefs/browser_prefs.h"
 #include "chrome/browser/profile_resetter/triggered_profile_resetter_factory.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_profile.h"
 #include "components/variations/entropy_provider.h"
@@ skipping 76 matching lines @@
   const wchar_t kExpectedToolName[] =
       L"ToolMcToolToolMcToolToolMcToolToolMcToolToolMcToolToolMcToolToolMcTool"
       L"ToolMcToolToolMcToolToolMcTool";
   SetRegTimestampAndToolName(kLongToolName, nullptr);
   TriggeredProfileResetter triggered_profile_resetter(&profile_);
   triggered_profile_resetter.Activate();
   EXPECT_TRUE(triggered_profile_resetter.HasResetTrigger());
   EXPECT_STREQ(kExpectedToolName,
                triggered_profile_resetter.GetResetToolName().c_str());
 }