Move StringPiece into the base namespace. It is colliding

chrome/browser/privacy_blacklist/blocked_response.cc

 // Copyright (c) 2009 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/privacy_blacklist/blocked_response.h"
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/logging.h"
 #include "base/values.h"
@@ skipping 22 matching lines @@
       }
     }
   } else {
     entry = match->entries().front();
   }
   DCHECK(entry);
 
   strings.SetString(L"name", entry->provider()->name());
   strings.SetString(L"url", entry->provider()->url());
 
-  const StringPiece html =
+  const base::StringPiece html =
     ResourceBundle::GetSharedInstance().GetRawDataResource(IDR_BLACKLIST_HTML);
   return jstemplate_builder::GetI18nTemplateHtml(html, &strings);
 }
 
 std::string GetImage(const Blacklist::Match*) {
   return ResourceBundle::GetSharedInstance().
       GetDataResource(IDR_BLACKLIST_IMAGE);
 }
 
 }  // namespace BlockedResponse