Introduce a MetricsDataProvider interface.

chrome/browser/metrics/metrics_log.h

 // Copyright (c) 2012 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.
 
 // This file defines a set of user experience metrics data recorded by
 // the MetricsService.  This is the unit of data that is sent to the server.
 
 #ifndef CHROME_BROWSER_METRICS_METRICS_LOG_H_
 #define CHROME_BROWSER_METRICS_METRICS_LOG_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_vector.h"
 #include "chrome/browser/metrics/extension_metrics.h"
 #include "chrome/browser/metrics/metrics_network_observer.h"
 #include "chrome/common/metrics/variations/variations_util.h"
 #include "chrome/installer/util/google_update_settings.h"
 #include "components/metrics/metrics_log_base.h"
 #include "ui/gfx/size.h"
 
 class HashedExtensionMetrics;
 class MetricsNetworkObserver;
 struct OmniboxLog;
 class PrefService;
 class PrefRegistrySimple;
 
 #if defined(OS_CHROMEOS)
 class MetricsLogChromeOS;
 #endif
 
 namespace base {
 class DictionaryValue;
 }
 
 namespace content {
 struct WebPluginInfo;
 }
 
+namespace metrics {
+class MetricsDataProvider;
+}
+
 namespace tracked_objects {
 struct ProcessDataSnapshot;
 }
 
 namespace chrome_variations {
 struct ActiveGroupId;
 }
 
 // This is a small helper struct to pass Google Update metrics in a single
 // reference argument to MetricsLog::RecordEnvironment().
@@ skipping 32 matching lines @@
   static void set_version_extension(const std::string& extension);
   static const std::string& version_extension();
 
   // Records the current operating environment.  Takes the list of installed
   // plugins, Google Update statistics, and synthetic trial IDs as parameters
   // because those can't be obtained synchronously from the UI thread.
   // A synthetic trial is one that is set up dynamically by code in Chrome. For
   // example, a pref may be mapped to a synthetic trial such that the group
   // is determined by the pref value.
   void RecordEnvironment(
+      const ScopedVector<metrics::MetricsDataProvider>& data_providers,

[Ilya Sherman, 2014/05/19 14:45:00]

nit: Passing ScopedVectors is a little odd.  Please pass the underlying
std::vector instead.  (Ditto throughout.)

[Ilya Sherman, 2014/05/19 14:45:00]

nit: Please update the docs.

[Alexei Svitkine (slow), 2014/05/19 15:23:02]

Didn't realise it's possible to access the underlying vector. Done.

[Alexei Svitkine (slow), 2014/05/19 15:23:02]

Done.

       const std::vector<content::WebPluginInfo>& plugin_list,
       const GoogleUpdateMetrics& google_update_metrics,
       const std::vector<chrome_variations::ActiveGroupId>& synthetic_trials);
 
   // Loads the environment proto that was saved by the last RecordEnvironment()
   // call from prefs and clears the pref value. Returns true on success or false
   // if there was no saved environment in prefs or it could not be decoded.
   bool LoadSavedEnvironmentFromPrefs();
 
   // Records the input text, available choices, and selected entry when the
   // user uses the Omnibox to open a URL.
   void RecordOmniboxOpenedURL(const OmniboxLog& log);
 
   // Records the passed profiled data, which should be a snapshot of the
   // browser's profiled performance during startup for a single process.
   void RecordProfilerData(
       const tracked_objects::ProcessDataSnapshot& process_data,
       int process_type);
 
   // Writes application stability metrics (as part of the profile log). The
   // system profile portion of the log must have already been filled in by a
   // call to RecordEnvironment() or LoadSavedEnvironmentFromPrefs().
   // NOTE: Has the side-effect of clearing the stability prefs..
   //
   // If this log is of type INITIAL_STABILITY_LOG, records additional info such
   // as number of incomplete shutdowns as well as extra breakpad and debugger
   // stats.
-  void RecordStabilityMetrics(base::TimeDelta incremental_uptime,
-                              base::TimeDelta uptime);
+  void RecordStabilityMetrics(
+      const ScopedVector<metrics::MetricsDataProvider>& data_providers,

[Ilya Sherman, 2014/05/19 14:45:00]

nit: Please update the docs.

[Alexei Svitkine (slow), 2014/05/19 15:23:02]

Done.

+      base::TimeDelta incremental_uptime,
+      base::TimeDelta uptime);
+
+  // Record general metrics based on the specified |providers|.
+  void RecordGeneralMetrics(
+      const ScopedVector<metrics::MetricsDataProvider>& data_providers);
 
   const base::TimeTicks& creation_time() const {
     return creation_time_;
   }
 
  protected:
   // Exposed for the sake of mocking in test code.
 
   // Returns the PrefService from which to log metrics data.
   virtual PrefService* GetPrefService();
@@ skipping 55 matching lines @@
   // The time when the current log was created.
   const base::TimeTicks creation_time_;
 
   // For including information on which extensions are installed in reports.
   HashedExtensionMetrics extension_metrics_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsLog);
 };
 
 #endif  // CHROME_BROWSER_METRICS_METRICS_LOG_H_