Revert 268232 "Refactor MetricsStateManager class out of Metrics..."

trunk/src/chrome/browser/metrics/metrics_service.h

Index: trunk/src/chrome/browser/metrics/metrics_service.h
===================================================================
--- trunk/src/chrome/browser/metrics/metrics_service.h	(revision 268245)
+++ trunk/src/chrome/browser/metrics/metrics_service.h	(working copy)
@@ -69,7 +69,7 @@
 }
 
 namespace metrics {
-class MetricsStateManager;
+class ClonedInstallDetector;
 }
 
 namespace net {
@@ -127,24 +127,26 @@
     SHUTDOWN_COMPLETE = 700,
   };
 
+  enum ReportingState {
+    REPORTING_ENABLED,
+    REPORTING_DISABLED,
+  };
+
   MetricsService();
   virtual ~MetricsService();
 
   // Initializes metrics recording state. Updates various bookkeeping values in
   // prefs and sets up the scheduler. This is a separate function rather than
   // being done by the constructor so that field trials could be created before
-  // this is run.
-  void InitializeMetricsRecordingState();
+  // this is run. Takes |reporting_state| parameter which specifies whether UMA
+  // is enabled.
+  void InitializeMetricsRecordingState(ReportingState reporting_state);
 
   // Starts the metrics system, turning on recording and uploading of metrics.
   // Should be called when starting up with metrics enabled, or when metrics
   // are turned on.
   void Start();
 
-  // If metrics reporting is enabled, starts the metrics service. Returns
-  // whether the metrics service was started.
-  bool StartIfMetricsReportingEnabled();
-
   // Starts the metrics system in a special test-only mode. Metrics won't ever
   // be uploaded or persisted in this mode, but metrics will be recorded in
   // memory.
@@ -167,13 +169,24 @@
 
   // Returns the preferred entropy provider used to seed persistent activities
   // based on whether or not metrics reporting will be permitted on this client.
+  // The caller must determine if metrics reporting will be enabled for this
+  // client and pass that state in as |reporting_will_be_enabled|.
   //
-  // If metrics reporting is enabled, this method returns an entropy provider
-  // that has a high source of entropy, partially based on the client ID.
-  // Otherwise, it returns an entropy provider that is based on a low entropy
-  // source.
-  scoped_ptr<const base::FieldTrial::EntropyProvider> CreateEntropyProvider();
+  // If |reporting_will_be_enabled| is true, this method returns an entropy
+  // provider that has a high source of entropy, partially based on the client
+  // ID. Otherwise, an entropy provider that is based on a low entropy source
+  // is returned.
+  //
+  // Note that this reporting state can not be checked by reporting_active()
+  // because this method may need to be called before the MetricsService needs
+  // to be started.
+  scoped_ptr<const base::FieldTrial::EntropyProvider> CreateEntropyProvider(
+      ReportingState reporting_state);
 
+  // Force the client ID to be generated. This is useful in case it's needed
+  // before recording.
+  void ForceClientIdCreation();
+
   // At startup, prefs needs to be called with a list of all the pref names and
   // types we'll be using.
   static void RegisterPrefs(PrefRegistrySimple* registry);
@@ -299,6 +312,15 @@
     NEED_TO_SHUTDOWN = ~CLEANLY_SHUTDOWN
   };
 
+  // Designates which entropy source was returned from this MetricsService.
+  // This is used for testing to validate that we return the correct source
+  // depending on the state of the service.
+  enum EntropySourceReturned {
+    LAST_ENTROPY_NONE,
+    LAST_ENTROPY_LOW,
+    LAST_ENTROPY_HIGH,
+  };
+
   struct ChildProcessStats;
 
   typedef std::vector<SyntheticTrialGroup> SyntheticTrialGroups;
@@ -346,6 +368,22 @@
                   base::TimeDelta* incremental_uptime,
                   base::TimeDelta* uptime);
 
+  // Reset the client id and low entropy source if the kMetricsResetMetricIDs
+  // pref is true.
+  void ResetMetricsIDsIfNecessary();
+
+  // Returns the low entropy source for this client. This is a random value
+  // that is non-identifying amongst browser clients. This method will
+  // generate the entropy source value if it has not been called before.
+  int GetLowEntropySource();
+
+  // Returns the first entropy source that was returned by this service since
+  // start up, or NONE if neither was returned yet. This is exposed for testing
+  // only.
+  EntropySourceReturned entropy_source_returned() const {
+    return entropy_source_returned_;
+  }
+
   // Turns recording on or off.
   // DisableRecording() also forces a persistent save of logging state (if
   // anything has been recorded, or transmitted).
@@ -359,8 +397,11 @@
   void HandleIdleSinceLastTransmission(bool in_idle);
 
   // Set up client ID, session ID, etc.
-  void InitializeMetricsState();
+  void InitializeMetricsState(ReportingState reporting_state);
 
+  // Generates a new client ID to use to identify self to metrics server.
+  static std::string GenerateClientID();
+
   // Schedule the next save of LocalState information.  This is called
   // automatically by the task that performs each save to schedule the next one.
   void ScheduleNextStateSave();
@@ -471,10 +512,6 @@
   void GetCurrentSyntheticFieldTrials(
       std::vector<chrome_variations::ActiveGroupId>* synthetic_trials);
 
-  // Used to manage various metrics reporting state prefs, such as client id,
-  // low entropy source and whether metrics reporting is enabled.
-  scoped_ptr<metrics::MetricsStateManager> state_manager_;
-
   base::ActionCallback action_callback_;
 
   content::NotificationRegistrar registrar_;
@@ -526,6 +563,12 @@
   // The HTTP pipelining test server.
   std::string http_pipelining_test_server_;
 
+  // The identifier that's sent to the server with the log reports.
+  std::string client_id_;
+
+  // The non-identifying low entropy source value.
+  int low_entropy_source_;
+
   // Whether the MetricsService object has received any notifications since
   // the last time a transmission was sent.
   bool idle_since_last_transmission_;
@@ -566,6 +609,9 @@
   scoped_refptr<chromeos::ExternalMetrics> external_metrics_;
 #endif
 
+  // The last entropy source returned by this service, used for testing.
+  EntropySourceReturned entropy_source_returned_;
+
   // Stores the time of the first call to |GetUptimes()|.
   base::TimeTicks first_updated_time_;
 
@@ -582,10 +628,19 @@
   // Field trial groups that map to Chrome configuration states.
   SyntheticTrialGroups synthetic_trial_groups_;
 
+  scoped_ptr<metrics::ClonedInstallDetector> cloned_install_detector_;
+
+  FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, ClientIdCorrectlyFormatted);
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, IsPluginProcess);
+  FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, LowEntropySource0NotReset);
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest,
                            PermutedEntropyCacheClearedWhenLowEntropyReset);
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, RegisterSyntheticTrial);
+  FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, ResetMetricsIDs);
+  FRIEND_TEST_ALL_PREFIXES(MetricsServiceBrowserTest,
+                           CheckLowEntropySourceUsed);
+  FRIEND_TEST_ALL_PREFIXES(MetricsServiceReportingTest,
+                           CheckHighEntropySourceUsed);
 
   DISALLOW_COPY_AND_ASSIGN(MetricsService);
 };
@@ -607,9 +662,6 @@
   FRIEND_TEST_ALL_PREFIXES(MetricsServiceTest, CrashReportingEnabled);
 
   // Returns true if prefs::kMetricsReportingEnabled is set.
-  // TODO(asvitkine): Consolidate the method in MetricsStateManager.
-  // TODO(asvitkine): This function does not report the correct value on
-  // Android and ChromeOS, see http://crbug.com/362192.
   static bool IsMetricsReportingEnabled();
 
   // Returns true if crash reporting is enabled.  This is set at the platform