base: Remove 'using' declaration of StringAppendV.

chrome/browser/sync/notifier/chrome_system_resources.cc

 // Copyright (c) 2010 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/sync/notifier/chrome_system_resources.h"
 
 #include <cstdlib>
 #include <cstring>
 #include <string>
 
@@ skipping 86 matching lines @@
       log_severity = logging::LOG_ERROR;
       break;
   }
   // We treat LOG(INFO) as VLOG(1).
   if ((log_severity >= logging::GetMinLogLevel()) &&
       ((log_severity != logging::LOG_INFO) ||
        (1 <= logging::GetVlogLevelHelper(file, ::strlen(file))))) {
     va_list ap;
     va_start(ap, format);
     std::string result;
-    StringAppendV(&result, format, ap);
+    base::StringAppendV(&result, format, ap);
     logging::LogMessage(file, line, log_severity).stream() << result;
     va_end(ap);
   }
 }
 
 void ChromeSystemResources::RunAndDeleteStorageCallback(
     invalidation::StorageCallback* callback) {
   callback->Run(true);
   delete callback;
 }
@@ skipping 29 matching lines @@
   return task_to_post;
 }
 
 void ChromeSystemResources::RunPostedTask(invalidation::Closure* task) {
   DCHECK(non_thread_safe_.CalledOnValidThread());
   RunAndDeleteClosure(task);
   posted_tasks_.erase(task);
 }
 
 }  // namespace sync_notifier