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

chrome/browser/chromeos/app_mode/fake_cws.cc

Index: chrome/browser/chromeos/app_mode/fake_cws.cc
diff --git a/chrome/browser/chromeos/app_mode/fake_cws.cc b/chrome/browser/chromeos/app_mode/fake_cws.cc
index b8d162913e22ec247cc2036078e0c5437e73bd3e..d58b07b15371ec367be86e60c244dff1f5c17ddf 100644
--- a/chrome/browser/chromeos/app_mode/fake_cws.cc
+++ b/chrome/browser/chromeos/app_mode/fake_cws.cc
@@ -191,8 +191,8 @@ bool FakeCWS::GetUpdateCheckContent(const std::vector<std::string>& ids,
 std::unique_ptr<HttpResponse> FakeCWS::HandleRequest(
     const HttpRequest& request) {
   GURL request_url = GURL("http://localhost").Resolve(request.relative_url);
-  std::string request_path = request_url.path();
-  if (request_path.find(update_check_end_point_) != std::string::npos &&
+  base::StringPiece request_path = request_url.path();
+  if (request_path.find(update_check_end_point_) != base::StringPiece::npos &&
       !id_to_update_check_content_map_.empty()) {
     std::vector<std::string> ids;
     if (GetAppIdsFromUpdateUrl(request_url, &ids)) {