Revert 257524 "Move IsStringASCII/UTF8 to base namespace."

trunk/src/chrome/browser/sync_file_system/drive_backend_v1/api_util.cc

 // Copyright 2013 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_file_system/drive_backend_v1/api_util.h"
 
 #include <algorithm>
 #include <functional>
 #include <sstream>
 #include <string>
@@ skipping 303 matching lines @@
                            directory_name,
                            callback));
 }
 
 void APIUtil::DidGetDirectory(const std::string& parent_resource_id,
                               const std::string& directory_name,
                               const ResourceIdCallback& callback,
                               google_apis::GDataErrorCode error,
                               scoped_ptr<google_apis::ResourceList> feed) {
   DCHECK(CalledOnValidThread());
-  DCHECK(base::IsStringASCII(directory_name));
+  DCHECK(IsStringASCII(directory_name));
 
   if (error != google_apis::HTTP_SUCCESS) {
     DVLOG(2) << "Error on getting Drive directory: " << error;
     callback.Run(error, std::string());
     return;
   }
 
   std::string resource_id;
   ParentType parent_type = PARENT_TYPE_DIRECTORY;
   if (parent_resource_id.empty()) {
@@ skipping 799 matching lines @@
 }
 
 std::string APIUtil::GetRootResourceId() const {
   if (IsDriveAPIDisabled())
     return drive_service_->GetRootResourceId();
   return root_resource_id_;
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system