Fixed all unused-variable Clang warnings on Windows.

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 40 matching lines @@
 using base::win::ScopedHandle;
 
 namespace {
 
 const wchar_t kChromeRegClientsKey[] =
     L"Software\\Google\\Update\\Clients\\"
     L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
 const wchar_t kChromeRegClientStateKey[] =
     L"Software\\Google\\Update\\ClientState\\"
     L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
-const wchar_t kChromeRegClientStateMediumKey[] =
-    L"Software\\Google\\Update\\ClientStateMedium\\"
-    L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
 
 const wchar_t kGCAPITempKey[] = L"Software\\Google\\GCAPITemp";
 
-const wchar_t kChromeRegLaunchCmd[] = L"InstallerSuccessLaunchCmdLine";
-const wchar_t kChromeRegLastLaunchCmd[] = L"LastInstallerSuccessLaunchCmdLine";
 const wchar_t kChromeRegVersion[] = L"pv";
 const wchar_t kNoChromeOfferUntil[] =
     L"SOFTWARE\\Google\\No Chrome Offer Until";
 
 const wchar_t kC1FPendingKey[] =
     L"Software\\Google\\Common\\Rlz\\Events\\C";
 const wchar_t kC1FSentKey[] =
     L"Software\\Google\\Common\\Rlz\\StatefulEvents\\C";
 const wchar_t kC1FKey[] = L"C1F";
 
@@ skipping 710 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;
 }