Introduce MetricsServiceClient::StartGatheringMetrics

components/metrics/metrics_service_client.h

 // 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.
 
 #ifndef COMPONENTS_METRICS_METRICS_SERVICE_CLIENT_H_
 #define COMPONENTS_METRICS_METRICS_SERVICE_CLIENT_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 24 matching lines @@
 
   // Returns the release channel (e.g. stable, beta, etc) of the application.
   virtual SystemProfileProto::Channel GetChannel() = 0;
 
   // Returns the version of the application as a string.
   virtual std::string GetVersionString() = 0;
 
   // Called by the metrics service when a log has been uploaded.
   virtual void OnLogUploadComplete() = 0;
 
+  // Starts gathering metrics, calling |done_callback| when initial metrics
+  // gathering is complete.
+  virtual void StartGatheringMetrics(const base::Closure& done_callback) = 0;
+
   // Called prior to a metrics log being closed, allowing the client to collect
   // extra histograms that will go in that log. Asynchronous API - the client
   // implementation should call |done_callback| when complete.
   virtual void CollectFinalMetrics(const base::Closure& done_callback) = 0;
 };
 
 }  // namespace metrics
 
 #endif  // COMPONENTS_METRICS_METRICS_SERVICE_CLIENT_H_