Revert of Revert of clang/win: Fix a few warnings in targets not in chromium_builder_tests.

chrome/installer/gcapi/gcapi.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.
 
 // NOTE: This code is a legacy utility API for partners to check whether
 //       Chrome can be installed and launched. Recent updates are being made
 //       to add new functionality. These updates use code from Chromium, the old
 //       coded against the win32 api directly. If you have an itch to shave a
 //       yak, feel free to re-write the old code too.
 
@@ skipping 654 matching lines @@
     if (HasBeenReactivated()) {
       if (error_code)
         *error_code = REACTIVATE_ERROR_ALREADY_REACTIVATED;
       return FALSE;
     }
   }
 
   return TRUE;
 }
 
-BOOL __stdcall ReactivateChrome(wchar_t* brand_code,
+BOOL __stdcall ReactivateChrome(const wchar_t* brand_code,
                                 int shell_mode,
                                 DWORD* error_code) {
   BOOL result = FALSE;
   if (CanOfferReactivation(brand_code,
                            shell_mode,
                            error_code)) {
     if (SetReactivationBrandCode(brand_code, shell_mode)) {
       // Currently set this as a best-effort thing. We return TRUE if
       // reactivation succeeded regardless of the experiment label result.
       SetReactivationExperimentLabels(brand_code, shell_mode);
@@ skipping 103 matching lines @@
       key.WriteValue(kRelaunchAllowedAfterValue,
                      FormatDateOffsetByMonths(6)) != ERROR_SUCCESS ||
       !SetRelaunchExperimentLabels(relaunch_brandcode, shell_mode)) {
     if (error_code)
       *error_code = RELAUNCH_ERROR_RELAUNCH_FAILED;
     return FALSE;
   }
 
   return TRUE;
 }