Use StringPiece for CreateUploader/NetMetricsLogUploader params.

components/metrics/test_metrics_service_client.cc

 // Copyright 2014 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 "components/metrics/test_metrics_service_client.h"
 
 #include <memory>
 
 #include "base/callback.h"
 #include "components/metrics/metrics_log_uploader.h"
@@ skipping 47 matching lines @@
     const base::Closure& done_callback) {
   done_callback.Run();
 }
 
 void TestMetricsServiceClient::CollectFinalMetricsForLog(
     const base::Closure& done_callback) {
   done_callback.Run();
 }
 
 std::unique_ptr<MetricsLogUploader> TestMetricsServiceClient::CreateUploader(
-    const std::string& server_url,
-    const std::string& mime_type,
+    base::StringPiece server_url,
+    base::StringPiece mime_type,
     MetricsLogUploader::MetricServiceType service_type,
     const base::Callback<void(int)>& on_upload_complete) {
-  uploader_ = new TestMetricsLogUploader(server_url, mime_type, service_type,
-                                         on_upload_complete);
+  uploader_ = new TestMetricsLogUploader(on_upload_complete);
   return std::unique_ptr<MetricsLogUploader>(uploader_);
 }
 
 base::TimeDelta TestMetricsServiceClient::GetStandardUploadInterval() {
   return base::TimeDelta::FromMinutes(5);
 }
 
 bool TestMetricsServiceClient::IsReportingPolicyManaged() {
   return reporting_is_managed_;
 }
 
 EnableMetricsDefault
 TestMetricsServiceClient::GetMetricsReportingDefaultState() {
   return enable_default_;
 }
 
 }  // namespace metrics