[WIP] make GURL::path() return a StringPiece

chrome/browser/extensions/api/developer_private/developer_private_mangle.cc

 // Copyright 2015 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/extensions/api/developer_private/developer_private_mangle.h"
 
 #include <memory>
 
 #include "base/values.h"
 #include "chrome/common/extensions/api/developer_private.h"
@@ skipping 86 matching lines @@
       severity = logging::LOG_ERROR;
     value->SetInteger("level", static_cast<int>(severity));
     result.runtime_errors.push_back(std::move(value));
   }
   result.offline_enabled = info.offline_enabled;
   for (const api::developer_private::ExtensionView& view : info.views) {
     api::developer_private::ItemInspectView view_copy;
     GURL url(view.url);
     if (url.scheme() == kExtensionScheme) {
       // No leading slash.
-      view_copy.path = url.path().substr(1);
+      view_copy.path = url.path().substr(1).as_string();
     } else {
       // For live pages, use the full URL.
       view_copy.path = url.spec();
     }
     view_copy.render_process_id = view.render_process_id;
     view_copy.render_view_id = view.render_view_id;
     view_copy.incognito = view.incognito;
     view_copy.generated_background_page =
         view_copy.path == kGeneratedBackgroundPageFilename;
     result.views.push_back(std::move(view_copy));
   }
 
   return result;
 }
 
 }  // namespace developer_private_mangle
 }  // namespace extensions