Refactor MetricsStateManager class out of MetricsService.

chrome/browser/metrics/metrics_state_manager.cc

Index: chrome/browser/metrics/metrics_state_manager.cc
===================================================================
--- chrome/browser/metrics/metrics_state_manager.cc	(working copy)
+++ chrome/browser/metrics/metrics_state_manager.cc	(working copy)
@@ -1,317 +1,28 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// 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.
 
-//------------------------------------------------------------------------------
-// Description of the life cycle of a instance of MetricsService.
-//
-//  OVERVIEW
-//
-// A MetricsService instance is typically created at application startup.  It is
-// the central controller for the acquisition of log data, and the automatic
-// transmission of that log data to an external server.  Its major job is to
-// manage logs, grouping them for transmission, and transmitting them.  As part
-// of its grouping, MS finalizes logs by including some just-in-time gathered
-// memory statistics, snapshotting the current stats of numerous histograms,
-// closing the logs, translating to protocol buffer format, and compressing the
-// results for transmission.  Transmission includes submitting a compressed log
-// as data in a URL-post, and retransmitting (or retaining at process
-// termination) if the attempted transmission failed.  Retention across process
-// terminations is done using the the PrefServices facilities. The retained logs
-// (the ones that never got transmitted) are compressed and base64-encoded
-// before being persisted.
-//
-// Logs fall into one of two categories: "initial logs," and "ongoing logs."
-// There is at most one initial log sent for each complete run of Chrome (from
-// startup, to browser shutdown).  An initial log is generally transmitted some
-// short time (1 minute?) after startup, and includes stats such as recent crash
-// info, the number and types of plugins, etc.  The external server's response
-// to the initial log conceptually tells this MS if it should continue
-// transmitting logs (during this session). The server response can actually be
-// much more detailed, and always includes (at a minimum) how often additional
-// ongoing logs should be sent.
-//
-// After the above initial log, a series of ongoing logs will be transmitted.
-// The first ongoing log actually begins to accumulate information stating when
-// the MS was first constructed.  Note that even though the initial log is
-// commonly sent a full minute after startup, the initial log does not include
-// much in the way of user stats.   The most common interlog period (delay)
-// is 30 minutes. That time period starts when the first user action causes a
-// logging event.  This means that if there is no user action, there may be long
-// periods without any (ongoing) log transmissions.  Ongoing logs typically
-// contain very detailed records of user activities (ex: opened tab, closed
-// tab, fetched URL, maximized window, etc.)  In addition, just before an
-// ongoing log is closed out, a call is made to gather memory statistics.  Those
-// memory statistics are deposited into a histogram, and the log finalization
-// code is then called.  In the finalization, a call to a Histogram server
-// acquires a list of all local histograms that have been flagged for upload
-// to the UMA server.  The finalization also acquires the most recent number
-// of page loads, along with any counts of renderer or plugin crashes.
-//
-// When the browser shuts down, there will typically be a fragment of an ongoing
-// log that has not yet been transmitted.  At shutdown time, that fragment is
-// closed (including snapshotting histograms), and persisted, for potential
-// transmission during a future run of the product.
-//
-// There are two slightly abnormal shutdown conditions.  There is a
-// "disconnected scenario," and a "really fast startup and shutdown" scenario.
-// In the "never connected" situation, the user has (during the running of the
-// process) never established an internet connection.  As a result, attempts to
-// transmit the initial log have failed, and a lot(?) of data has accumulated in
-// the ongoing log (which didn't yet get closed, because there was never even a
-// contemplation of sending it).  There is also a kindred "lost connection"
-// situation, where a loss of connection prevented an ongoing log from being
-// transmitted, and a (still open) log was stuck accumulating a lot(?) of data,
-// while the earlier log retried its transmission.  In both of these
-// disconnected situations, two logs need to be, and are, persistently stored
-// for future transmission.
-//
-// The other unusual shutdown condition, termed "really fast startup and
-// shutdown," involves the deliberate user termination of the process before
-// the initial log is even formed or transmitted. In that situation, no logging
-// is done, but the historical crash statistics remain (unlogged) for inclusion
-// in a future run's initial log.  (i.e., we don't lose crash stats).
-//
-// With the above overview, we can now describe the state machine's various
-// states, based on the State enum specified in the state_ member.  Those states
-// are:
-//
-//  INITIALIZED,                   // Constructor was called.
-//  INIT_TASK_SCHEDULED,           // Waiting for deferred init tasks to finish.
-//  INIT_TASK_DONE,                // Waiting for timer to send initial log.
-//  SENDING_INITIAL_STABILITY_LOG, // Initial stability log being sent.
-//  SENDING_INITIAL_METRICS_LOG,   // Initial metrics log being sent.
-//  SENDING_OLD_LOGS,              // Sending unsent logs from previous session.
-//  SENDING_CURRENT_LOGS,          // Sending ongoing logs as they acrue.
-//
-// In more detail, we have:
-//
-//    INITIALIZED,            // Constructor was called.
-// The MS has been constructed, but has taken no actions to compose the
-// initial log.
-//
-//    INIT_TASK_SCHEDULED,    // Waiting for deferred init tasks to finish.
-// Typically about 30 seconds after startup, a task is sent to a second thread
-// (the file thread) to perform deferred (lower priority and slower)
-// initialization steps such as getting the list of plugins.  That task will
-// (when complete) make an async callback (via a Task) to indicate the
-// completion.
-//
-//    INIT_TASK_DONE,         // Waiting for timer to send initial log.
-// The callback has arrived, and it is now possible for an initial log to be
-// created.  This callback typically arrives back less than one second after
-// the deferred init task is dispatched.
-//
-//    SENDING_INITIAL_STABILITY_LOG,  // Initial stability log being sent.
-// During initialization, if a crash occurred during the previous session, an
-// initial stability log will be generated and registered with the log manager.
-// This state will be entered if a stability log was prepared during metrics
-// service initialization (in InitializeMetricsRecordingState()) and is waiting
-// to be transmitted when it's time to send up the first log (per the reporting
-// scheduler).  If there is no initial stability log (e.g. there was no previous
-// crash), then this state will be skipped and the state will advance to
-// SENDING_INITIAL_METRICS_LOG.
-//
-//    SENDING_INITIAL_METRICS_LOG,  // Initial metrics log being sent.
-// This state is entered after the initial metrics log has been composed, and
-// prepared for transmission.  This happens after SENDING_INITIAL_STABILITY_LOG
-// if there was an initial stability log (see above).  It is also the case that
-// any previously unsent logs have been loaded into instance variables for
-// possible transmission.
-//
-//    SENDING_OLD_LOGS,       // Sending unsent logs from previous session.
-// This state indicates that the initial log for this session has been
-// successfully sent and it is now time to send any logs that were
-// saved from previous sessions.  All such logs will be transmitted before
-// exiting this state, and proceeding with ongoing logs from the current session
-// (see next state).
-//
-//    SENDING_CURRENT_LOGS,   // Sending standard current logs as they accrue.
-// Current logs are being accumulated.  Typically every 20 minutes a log is
-// closed and finalized for transmission, at the same time as a new log is
-// started.
-//
-// The progression through the above states is simple, and sequential, in the
-// most common use cases.  States proceed from INITIAL to SENDING_CURRENT_LOGS,
-// and remain in the latter until shutdown.
-//
-// The one unusual case is when the user asks that we stop logging.  When that
-// happens, any staged (transmission in progress) log is persisted, and any log
-// that is currently accumulating is also finalized and persisted.  We then
-// regress back to the SEND_OLD_LOGS state in case the user enables log
-// recording again during this session.  This way anything we have persisted
-// will be sent automatically if/when we progress back to SENDING_CURRENT_LOG
-// state.
-//
-// Another similar case is on mobile, when the application is backgrounded and
-// then foregrounded again. Backgrounding created new "old" stored logs, so the
-// state drops back from SENDING_CURRENT_LOGS to SENDING_OLD_LOGS so those logs
-// will be sent.
-//
-// Also note that whenever we successfully send an old log, we mirror the list
-// of logs into the PrefService. This ensures that IF we crash, we won't start
-// up and retransmit our old logs again.
-//
-// Due to race conditions, it is always possible that a log file could be sent
-// twice.  For example, if a log file is sent, but not yet acknowledged by
-// the external server, and the user shuts down, then a copy of the log may be
-// saved for re-transmission.  These duplicates could be filtered out server
-// side, but are not expected to be a significant problem.
-//
-//
-//------------------------------------------------------------------------------
+#include "chrome/browser/metrics/metrics_state_manager.h"
 
-#include "chrome/browser/metrics/metrics_service.h"
-
-#include <algorithm>
-
-#include "base/bind.h"
-#include "base/callback.h"
 #include "base/command_line.h"
 #include "base/guid.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
-#include "base/metrics/statistics_recorder.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
-#include "base/prefs/scoped_user_pref_update.h"
 #include "base/rand_util.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/strings/utf_string_conversions.h"
-#include "base/threading/platform_thread.h"
-#include "base/threading/thread.h"
-#include "base/threading/thread_restrictions.h"
-#include "base/tracked_objects.h"
-#include "base/values.h"
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/io_thread.h"
-#include "chrome/browser/memory_details.h"
+#include "base/time/time.h"
 #include "chrome/browser/metrics/cloned_install_detector.h"
-#include "chrome/browser/metrics/compression_utils.h"
 #include "chrome/browser/metrics/machine_id_provider.h"
-#include "chrome/browser/metrics/metrics_log.h"
-#include "chrome/browser/metrics/metrics_log_serializer.h"
-#include "chrome/browser/metrics/metrics_reporting_scheduler.h"
-#include "chrome/browser/metrics/time_ticks_experiment_win.h"
-#include "chrome/browser/metrics/tracking_synchronizer.h"
-#include "chrome/common/metrics/variations/variations_util.h"
-#include "chrome/browser/net/http_pipelining_compatibility_client.h"
-#include "chrome/browser/net/network_stats.h"
-#include "chrome/browser/omnibox/omnibox_log.h"
-#include "chrome/browser/ui/browser_list.h"
-#include "chrome/browser/ui/browser_otr_state.h"
-#include "chrome/browser/ui/search/search_tab_helper.h"
-#include "chrome/common/chrome_constants.h"
-#include "chrome/common/chrome_result_codes.h"
 #include "chrome/common/chrome_switches.h"
-#include "chrome/common/crash_keys.h"
 #include "chrome/common/metrics/caching_permuted_entropy_provider.h"
-#include "chrome/common/metrics/metrics_log_manager.h"
-#include "chrome/common/net/test_server_locations.h"
 #include "chrome/common/pref_names.h"
-#include "chrome/common/render_messages.h"
-#include "components/variations/entropy_provider.h"
-#include "components/variations/metrics_util.h"
-#include "content/public/browser/child_process_data.h"
-#include "content/public/browser/histogram_fetcher.h"
-#include "content/public/browser/load_notification_details.h"
-#include "content/public/browser/notification_service.h"
-#include "content/public/browser/plugin_service.h"
-#include "content/public/browser/render_process_host.h"
-#include "content/public/browser/user_metrics.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/common/process_type.h"
-#include "content/public/common/webplugininfo.h"
-#include "extensions/browser/process_map.h"
-#include "net/base/load_flags.h"
-#include "net/url_request/url_fetcher.h"
 
-// TODO(port): port browser_distribution.h.
-#if !defined(OS_POSIX)
-#include "chrome/installer/util/browser_distribution.h"
-#endif
+namespace metrics {
 
-#if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/external_metrics.h"
-#include "chrome/browser/chromeos/settings/cros_settings.h"
-#include "chromeos/system/statistics_provider.h"
-#endif
-
-#if defined(OS_WIN)
-#include <windows.h>  // Needed for STATUS_* codes
-#include "base/win/registry.h"
-#endif
-
-#if !defined(OS_ANDROID)
-#include "chrome/browser/service_process/service_process_control.h"
-#endif
-
-using base::Time;
-using content::BrowserThread;
-using content::ChildProcessData;
-using content::LoadNotificationDetails;
-using content::PluginService;
-
 namespace {
 
-// Check to see that we're being called on only one thread.
-bool IsSingleThreaded() {
-  static base::PlatformThreadId thread_id = 0;
-  if (!thread_id)
-    thread_id = base::PlatformThread::CurrentId();
-  return base::PlatformThread::CurrentId() == thread_id;
-}
-
-// The delay, in seconds, after starting recording before doing expensive
-// initialization work.
-#if defined(OS_ANDROID) || defined(OS_IOS)
-// On mobile devices, a significant portion of sessions last less than a minute.
-// Use a shorter timer on these platforms to avoid losing data.
-// TODO(dfalcantara): To avoid delaying startup, tighten up initialization so
-//                    that it occurs after the user gets their initial page.
-const int kInitializationDelaySeconds = 5;
-#else
-const int kInitializationDelaySeconds = 30;
-#endif
-
-// This specifies the amount of time to wait for all renderers to send their
-// data.
-const int kMaxHistogramGatheringWaitDuration = 60000;  // 60 seconds.
-
-// The maximum number of events in a log uploaded to the UMA server.
-const int kEventLimit = 2400;
-
-// If an upload fails, and the transmission was over this byte count, then we
-// will discard the log, and not try to retransmit it.  We also don't persist
-// the log to the prefs for transmission during the next chrome session if this
-// limit is exceeded.
-const size_t kUploadLogAvoidRetransmitSize = 50000;
-
-// Interval, in minutes, between state saves.
-const int kSaveStateIntervalMinutes = 5;
-
-enum ResponseStatus {
-  UNKNOWN_FAILURE,
-  SUCCESS,
-  BAD_REQUEST,  // Invalid syntax or log too large.
-  NO_RESPONSE,
-  NUM_RESPONSE_STATUSES
-};
-
-ResponseStatus ResponseCodeToStatus(int response_code) {
-  switch (response_code) {
-    case 200:
-      return SUCCESS;
-    case 400:
-      return BAD_REQUEST;
-    case net::URLFetcher::RESPONSE_CODE_INVALID:
-      return NO_RESPONSE;
-    default:
-      return UNKNOWN_FAILURE;
-  }
-}
-
 // The argument used to generate a non-identifying entropy source. We want no
 // more than 13 bits of entropy, so use this max to return a number in the range
 // [0, 7999] as the entropy source (12.97 bits of entropy).
@@ -327,241 +38,78 @@
   return base::RandInt(0, kMaxLowEntropySize - 1);
 }
 
-// Converts an exit code into something that can be inserted into our
-// histograms (which expect non-negative numbers less than MAX_INT).
-int MapCrashExitCodeForHistogram(int exit_code) {
-#if defined(OS_WIN)
-  // Since |abs(STATUS_GUARD_PAGE_VIOLATION) == MAX_INT| it causes problems in
-  // histograms.cc. Solve this by remapping it to a smaller value, which
-  // hopefully doesn't conflict with other codes.
-  if (exit_code == STATUS_GUARD_PAGE_VIOLATION)
-    return 0x1FCF7EC3;  // Randomly picked number.
-#endif
-
-  return std::abs(exit_code);
-}
-
-void MarkAppCleanShutdownAndCommit() {
-  PrefService* pref = g_browser_process->local_state();
-  pref->SetBoolean(prefs::kStabilityExitedCleanly, true);
-  pref->SetInteger(prefs::kStabilityExecutionPhase,
-                   MetricsService::SHUTDOWN_COMPLETE);
-  // Start writing right away (write happens on a different thread).
-  pref->CommitPendingWrite();
-}
-
 }  // namespace
 
-
-SyntheticTrialGroup::SyntheticTrialGroup(uint32 trial, uint32 group) {
-  id.name = trial;
-  id.group = group;
+MetricsStateManager::MetricsStateManager(PrefService* local_state)
+    : local_state_(local_state),
+      low_entropy_source_(kLowEntropySourceNotSet),
+      entropy_source_returned_(ENTROPY_SOURCE_NONE) {
+  ResetMetricsIDsIfNecessary();
+  if (IsMetricsReportingEnabled())
+    ForceClientIdCreation();
 }
 
-SyntheticTrialGroup::~SyntheticTrialGroup() {
+MetricsStateManager::~MetricsStateManager() {
 }
 
-// static
-MetricsService::ShutdownCleanliness MetricsService::clean_shutdown_status_ =
-    MetricsService::CLEANLY_SHUTDOWN;
+bool MetricsStateManager::IsMetricsReportingEnabled() {
+  // If the user permits metrics reporting with the checkbox in the
+  // prefs, we turn on recording.  We disable metrics completely for
+  // non-official builds.  This can be forced with a flag.
+  const CommandLine* command_line = CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(switches::kEnableMetricsReportingForTesting))
+    return true;
 
-MetricsService::ExecutionPhase MetricsService::execution_phase_ =
-    MetricsService::UNINITIALIZED_PHASE;
+  bool enabled = false;

[Ilya Sherman, 2014/05/02 19:35:06]

nit: Let's move this down by a few lines, to be declared a little closer to
where it's used.

[Alexei Svitkine (slow), 2014/05/02 20:21:32]

Done.

+  // Disable metrics reporting when field trials are forced.
+  if (command_line->HasSwitch(switches::kForceFieldTrials))
+    return false;
 
-// This is used to quickly log stats from child process related notifications in
-// MetricsService::child_stats_buffer_.  The buffer's contents are transferred
-// out when Local State is periodically saved.  The information is then
-// reported to the UMA server on next launch.
-struct MetricsService::ChildProcessStats {
- public:
-  explicit ChildProcessStats(int process_type)
-      : process_launches(0),
-        process_crashes(0),
-        instances(0),
-        loading_errors(0),
-        process_type(process_type) {}
-
-  // This constructor is only used by the map to return some default value for
-  // an index for which no value has been assigned.
-  ChildProcessStats()
-      : process_launches(0),
-        process_crashes(0),
-        instances(0),
-        loading_errors(0),
-        process_type(content::PROCESS_TYPE_UNKNOWN) {}
-
-  // The number of times that the given child process has been launched
-  int process_launches;
-
-  // The number of times that the given child process has crashed
-  int process_crashes;
-
-  // The number of instances of this child process that have been created.
-  // An instance is a DOM object rendered by this child process during a page
-  // load.
-  int instances;
-
-  // The number of times there was an error loading an instance of this child
-  // process.
-  int loading_errors;
-
-  int process_type;
-};
-
-// Handles asynchronous fetching of memory details.
-// Will run the provided task after finished.
-class MetricsMemoryDetails : public MemoryDetails {
- public:
-  explicit MetricsMemoryDetails(const base::Closure& callback)
-      : callback_(callback) {}
-
-  virtual void OnDetailsAvailable() OVERRIDE {
-    base::MessageLoop::current()->PostTask(FROM_HERE, callback_);
-  }
-
- private:
-  virtual ~MetricsMemoryDetails() {}
-
-  base::Closure callback_;
-  DISALLOW_COPY_AND_ASSIGN(MetricsMemoryDetails);
-};
-
-// static
-void MetricsService::RegisterPrefs(PrefRegistrySimple* registry) {
-  DCHECK(IsSingleThreaded());
-  registry->RegisterBooleanPref(prefs::kMetricsResetIds, false);
-  registry->RegisterStringPref(prefs::kMetricsClientID, std::string());
-  registry->RegisterInt64Pref(prefs::kMetricsReportingEnabledTimestamp, 0);
-  registry->RegisterIntegerPref(prefs::kMetricsLowEntropySource,
-                                kLowEntropySourceNotSet);
-  registry->RegisterInt64Pref(prefs::kStabilityLaunchTimeSec, 0);
-  registry->RegisterInt64Pref(prefs::kStabilityLastTimestampSec, 0);
-  registry->RegisterStringPref(prefs::kStabilityStatsVersion, std::string());
-  registry->RegisterInt64Pref(prefs::kStabilityStatsBuildTime, 0);
-  registry->RegisterBooleanPref(prefs::kStabilityExitedCleanly, true);
-  registry->RegisterIntegerPref(prefs::kStabilityExecutionPhase,
-                                UNINITIALIZED_PHASE);
-  registry->RegisterBooleanPref(prefs::kStabilitySessionEndCompleted, true);
-  registry->RegisterIntegerPref(prefs::kMetricsSessionID, -1);
-  registry->RegisterIntegerPref(prefs::kStabilityLaunchCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityCrashCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityIncompleteSessionEndCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityPageLoadCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityRendererCrashCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityExtensionRendererCrashCount,
-                                0);
-  registry->RegisterIntegerPref(prefs::kStabilityRendererHangCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityChildProcessCrashCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityBreakpadRegistrationFail, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityBreakpadRegistrationSuccess,
-                                0);
-  registry->RegisterIntegerPref(prefs::kStabilityDebuggerPresent, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityDebuggerNotPresent, 0);
+#if defined(GOOGLE_CHROME_BUILD)
 #if defined(OS_CHROMEOS)
-  registry->RegisterIntegerPref(prefs::kStabilityOtherUserCrashCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilityKernelCrashCount, 0);
-  registry->RegisterIntegerPref(prefs::kStabilitySystemUncleanShutdownCount, 0);
-#endif  // OS_CHROMEOS
-
-  registry->RegisterStringPref(prefs::kStabilitySavedSystemProfile,
-                               std::string());
-  registry->RegisterStringPref(prefs::kStabilitySavedSystemProfileHash,
-                               std::string());
-
-  registry->RegisterListPref(prefs::kMetricsInitialLogs);
-  registry->RegisterListPref(prefs::kMetricsOngoingLogs);
-
-  registry->RegisterInt64Pref(prefs::kInstallDate, 0);
-  registry->RegisterInt64Pref(prefs::kUninstallMetricsPageLoadCount, 0);
-  registry->RegisterInt64Pref(prefs::kUninstallLaunchCount, 0);
-  registry->RegisterInt64Pref(prefs::kUninstallMetricsUptimeSec, 0);
-  registry->RegisterInt64Pref(prefs::kUninstallLastLaunchTimeSec, 0);
-  registry->RegisterInt64Pref(prefs::kUninstallLastObservedRunTimeSec, 0);
-
-  // TODO(asvitkine): Remove these once a couple of releases have passed.
-  // http://crbug.com/357704
-  registry->RegisterStringPref(prefs::kMetricsOldClientID, std::string());
-  registry->RegisterIntegerPref(prefs::kMetricsOldLowEntropySource, 0);
-
-#if defined(OS_ANDROID)
-  RegisterPrefsAndroid(registry);
-#endif  // defined(OS_ANDROID)
+  chromeos::CrosSettings::Get()->GetBoolean(chromeos::kStatsReportingPref,
+                                            &enabled);
+#else
+  enabled = local_state->GetBoolean(prefs::kMetricsReportingEnabled);
+#endif  // #if defined(OS_CHROMEOS)
+#endif  // defined(GOOGLE_CHROME_BUILD)
+  return enabled;
 }
 
-MetricsService::MetricsService()
-    : metrics_ids_reset_check_performed_(false),
-      recording_active_(false),
-      reporting_active_(false),
-      test_mode_active_(false),
-      state_(INITIALIZED),
-      has_initial_stability_log_(false),
-      low_entropy_source_(kLowEntropySourceNotSet),
-      idle_since_last_transmission_(false),
-      session_id_(-1),
-      next_window_id_(0),
-      self_ptr_factory_(this),
-      state_saver_factory_(this),
-      waiting_for_asynchronous_reporting_step_(false),
-      num_async_histogram_fetches_in_progress_(0),
-      entropy_source_returned_(LAST_ENTROPY_NONE) {
-  DCHECK(IsSingleThreaded());
+void MetricsStateManager::ForceClientIdCreation() {
+  if (!client_id_.empty())
+    return;
 
-  log_manager_.set_log_serializer(new MetricsLogSerializer);
-  log_manager_.set_max_ongoing_log_store_size(kUploadLogAvoidRetransmitSize);
+  client_id_ = local_state_->GetString(prefs::kMetricsClientID);
+  if (!client_id_.empty())
+    return;
 
-  BrowserChildProcessObserver::Add(this);
-}
+  client_id_ = base::GenerateGUID();
+  local_state_->SetString(prefs::kMetricsClientID, client_id_);
 
-MetricsService::~MetricsService() {
-  DisableRecording();
-
-  BrowserChildProcessObserver::Remove(this);
+  if (local_state_->GetString(prefs::kMetricsOldClientID).empty()) {
+    // Record the timestamp of when the user opted in to UMA.
+    local_state_->SetInt64(prefs::kMetricsReportingEnabledTimestamp,
+                           base::Time::Now().ToTimeT());
+  } else {
+    UMA_HISTOGRAM_BOOLEAN("UMA.ClientIdMigrated", true);
+  }
+  local_state_->ClearPref(prefs::kMetricsOldClientID);
 }
 
-void MetricsService::InitializeMetricsRecordingState(
-    ReportingState reporting_state) {
-  InitializeMetricsState(reporting_state);
+void MetricsStateManager::CheckForClonedInstall() {
+  DCHECK(!cloned_install_detector_);
 
-  base::Closure callback = base::Bind(&MetricsService::StartScheduledUpload,
-                                      self_ptr_factory_.GetWeakPtr());
-  scheduler_.reset(new MetricsReportingScheduler(callback));
-}
-
-void MetricsService::Start() {
-  HandleIdleSinceLastTransmission(false);
-  EnableRecording();
-  EnableReporting();
-}
-
-void MetricsService::StartRecordingForTests() {
-  test_mode_active_ = true;
-  EnableRecording();
-  DisableReporting();
-}
-
-void MetricsService::Stop() {
-  HandleIdleSinceLastTransmission(false);
-  DisableReporting();
-  DisableRecording();
-}
-
-void MetricsService::EnableReporting() {
-  if (reporting_active_)
+  MachineIdProvider* provider = MachineIdProvider::CreateInstance();
+  if (!provider)
     return;
-  reporting_active_ = true;
-  StartSchedulerIfNecessary();
-}
 
-void MetricsService::DisableReporting() {
-  reporting_active_ = false;
+  cloned_install_detector_.reset(new ClonedInstallDetector(provider));
+  cloned_install_detector_->CheckForClonedInstall(local_state_);
 }
 
-std::string MetricsService::GetClientId() {
-  return client_id_;
-}
-
 scoped_ptr<const base::FieldTrial::EntropyProvider>
-MetricsService::CreateEntropyProvider(ReportingState reporting_state) {
+MetricsStateManager::CreateEntropyProvider() {
   // For metrics reporting-enabled users, we combine the client ID and low
   // entropy source to get the final entropy source. Otherwise, only use the low
   // entropy source.
@@ -572,621 +120,61 @@
   const int low_entropy_source_value = GetLowEntropySource();
   UMA_HISTOGRAM_SPARSE_SLOWLY("UMA.LowEntropySourceValue",
                               low_entropy_source_value);
-  if (reporting_state == REPORTING_ENABLED) {
-    if (entropy_source_returned_ == LAST_ENTROPY_NONE)
-      entropy_source_returned_ = LAST_ENTROPY_HIGH;
-    DCHECK_EQ(LAST_ENTROPY_HIGH, entropy_source_returned_);
+  if (IsMetricsReportingEnabled()) {
+    if (entropy_source_returned_ == ENTROPY_SOURCE_NONE)
+      entropy_source_returned_ = ENTROPY_SOURCE_HIGH;
+    DCHECK_EQ(ENTROPY_SOURCE_HIGH, entropy_source_returned_);
     const std::string high_entropy_source =
         client_id_ + base::IntToString(low_entropy_source_value);
     return scoped_ptr<const base::FieldTrial::EntropyProvider>(
-        new metrics::SHA1EntropyProvider(high_entropy_source));
+        new SHA1EntropyProvider(high_entropy_source));
   }
 
-  if (entropy_source_returned_ == LAST_ENTROPY_NONE)
-    entropy_source_returned_ = LAST_ENTROPY_LOW;
-  DCHECK_EQ(LAST_ENTROPY_LOW, entropy_source_returned_);
+  if (entropy_source_returned_ == ENTROPY_SOURCE_NONE)
+    entropy_source_returned_ = ENTROPY_SOURCE_LOW;
+  DCHECK_EQ(ENTROPY_SOURCE_LOW, entropy_source_returned_);
 
 #if defined(OS_ANDROID) || defined(OS_IOS)
   return scoped_ptr<const base::FieldTrial::EntropyProvider>(
-      new metrics::CachingPermutedEntropyProvider(
-          g_browser_process->local_state(),
-          low_entropy_source_value,
-          kMaxLowEntropySize));
+      new CachingPermutedEntropyProvider(local_state_,
+                                         low_entropy_source_value,
+                                         kMaxLowEntropySize));
 #else
   return scoped_ptr<const base::FieldTrial::EntropyProvider>(
-      new metrics::PermutedEntropyProvider(low_entropy_source_value,
-                                           kMaxLowEntropySize));
+      new PermutedEntropyProvider(low_entropy_source_value,
+                                  kMaxLowEntropySize));
 #endif
 }
 
-void MetricsService::ForceClientIdCreation() {
-  if (!client_id_.empty())
-    return;
-
-  ResetMetricsIDsIfNecessary();
-
-  PrefService* pref = g_browser_process->local_state();
-  client_id_ = pref->GetString(prefs::kMetricsClientID);
-  if (!client_id_.empty())
-    return;
-
-  client_id_ = GenerateClientID();
-  pref->SetString(prefs::kMetricsClientID, client_id_);
-
-  if (pref->GetString(prefs::kMetricsOldClientID).empty()) {
-    // Record the timestamp of when the user opted in to UMA.
-    pref->SetInt64(prefs::kMetricsReportingEnabledTimestamp,
-                   Time::Now().ToTimeT());
-  } else {
-    UMA_HISTOGRAM_BOOLEAN("UMA.ClientIdMigrated", true);
-  }
-  pref->ClearPref(prefs::kMetricsOldClientID);
-}
-
-void MetricsService::EnableRecording() {
-  DCHECK(IsSingleThreaded());
-
-  if (recording_active_)
-    return;
-  recording_active_ = true;
-
-  ForceClientIdCreation();
-  crash_keys::SetClientID(client_id_);
-  if (!log_manager_.current_log())
-    OpenNewLog();
-
-  SetUpNotifications(&registrar_, this);
-  base::RemoveActionCallback(action_callback_);
-  action_callback_ = base::Bind(&MetricsService::OnUserAction,
-                                base::Unretained(this));
-  base::AddActionCallback(action_callback_);
-}
-
-void MetricsService::DisableRecording() {
-  DCHECK(IsSingleThreaded());
-
-  if (!recording_active_)
-    return;
-  recording_active_ = false;
-
-  base::RemoveActionCallback(action_callback_);
-  registrar_.RemoveAll();
-  PushPendingLogsToPersistentStorage();
-  DCHECK(!log_manager_.has_staged_log());
-}
-
-bool MetricsService::recording_active() const {
-  DCHECK(IsSingleThreaded());
-  return recording_active_;
-}
-
-bool MetricsService::reporting_active() const {
-  DCHECK(IsSingleThreaded());
-  return reporting_active_;
-}
-
 // static
-void MetricsService::SetUpNotifications(
-    content::NotificationRegistrar* registrar,
-    content::NotificationObserver* observer) {
-  registrar->Add(observer, chrome::NOTIFICATION_BROWSER_OPENED,
-                 content::NotificationService::AllBrowserContextsAndSources());
-  registrar->Add(observer, chrome::NOTIFICATION_BROWSER_CLOSED,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, chrome::NOTIFICATION_TAB_PARENTED,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, chrome::NOTIFICATION_TAB_CLOSING,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, content::NOTIFICATION_LOAD_START,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, content::NOTIFICATION_LOAD_STOP,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, content::NOTIFICATION_RENDER_WIDGET_HOST_HANG,
-                 content::NotificationService::AllSources());
-  registrar->Add(observer, chrome::NOTIFICATION_OMNIBOX_OPENED_URL,
-                 content::NotificationService::AllSources());
-}
+void MetricsStateManager::RegisterPrefs(PrefRegistrySimple* registry) {
+  registry->RegisterBooleanPref(prefs::kMetricsResetIds, false);
+  registry->RegisterStringPref(prefs::kMetricsClientID, std::string());
+  registry->RegisterInt64Pref(prefs::kMetricsReportingEnabledTimestamp, 0);
+  registry->RegisterIntegerPref(prefs::kMetricsLowEntropySource,
+                                kLowEntropySourceNotSet);
 
-void MetricsService::BrowserChildProcessHostConnected(
-    const content::ChildProcessData& data) {
-  GetChildProcessStats(data).process_launches++;
-}
+  ClonedInstallDetector::RegisterPrefs(registry);
+  CachingPermutedEntropyProvider::RegisterPrefs(registry);
 
-void MetricsService::BrowserChildProcessCrashed(
-    const content::ChildProcessData& data) {
-  GetChildProcessStats(data).process_crashes++;
-  // Exclude plugin crashes from the count below because we report them via
-  // a separate UMA metric.
-  if (!IsPluginProcess(data.process_type))
-    IncrementPrefValue(prefs::kStabilityChildProcessCrashCount);
+  // TODO(asvitkine): Remove these once a couple of releases have passed.
+  // http://crbug.com/357704
+  registry->RegisterStringPref(prefs::kMetricsOldClientID, std::string());
+  registry->RegisterIntegerPref(prefs::kMetricsOldLowEntropySource, 0);
 }
 
-void MetricsService::BrowserChildProcessInstanceCreated(
-    const content::ChildProcessData& data) {
-  GetChildProcessStats(data).instances++;
-}
-
-void MetricsService::Observe(int type,
-                             const content::NotificationSource& source,
-                             const content::NotificationDetails& details) {
-  DCHECK(log_manager_.current_log());
-  DCHECK(IsSingleThreaded());
-
-  // Check for notifications related to core stability metrics, or that are
-  // just triggers to end idle mode. Anything else should be added in the later
-  // switch statement, where they take effect only if general metrics should be
-  // logged.
-  bool handled = false;
-  switch (type) {
-    case chrome::NOTIFICATION_BROWSER_OPENED:
-    case chrome::NOTIFICATION_BROWSER_CLOSED:
-    case chrome::NOTIFICATION_TAB_PARENTED:
-    case chrome::NOTIFICATION_TAB_CLOSING:
-    case content::NOTIFICATION_LOAD_STOP:
-      // These notifications are used only to break out of idle mode.
-      handled = true;
-      break;
-
-    case content::NOTIFICATION_LOAD_START: {
-      content::NavigationController* controller =
-          content::Source<content::NavigationController>(source).ptr();
-      content::WebContents* web_contents = controller->GetWebContents();
-      LogLoadStarted(web_contents);
-      handled = true;
-      break;
-    }
-
-    case content::NOTIFICATION_RENDERER_PROCESS_CLOSED: {
-      content::RenderProcessHost::RendererClosedDetails* process_details =
-          content::Details<
-              content::RenderProcessHost::RendererClosedDetails>(
-                  details).ptr();
-      content::RenderProcessHost* host =
-          content::Source<content::RenderProcessHost>(source).ptr();
-      LogRendererCrash(
-          host, process_details->status, process_details->exit_code);
-      handled = true;
-      break;
-    }
-
-    case content::NOTIFICATION_RENDER_WIDGET_HOST_HANG:
-      LogRendererHang();
-      handled = true;
-      break;
-
-    default:
-      // Everything else is handled after the early return check below.
-      break;
-  }
-
-  // If it wasn't one of the stability-related notifications, and event
-  // logging isn't suppressed, handle it.
-  if (!handled && ShouldLogEvents()) {
-    switch (type) {
-      case chrome::NOTIFICATION_OMNIBOX_OPENED_URL: {
-        MetricsLog* current_log =
-            static_cast<MetricsLog*>(log_manager_.current_log());
-        DCHECK(current_log);
-        current_log->RecordOmniboxOpenedURL(
-            *content::Details<OmniboxLog>(details).ptr());
-        break;
-      }
-
-      default:
-        NOTREACHED();
-        break;
-    }
-  }
-
-  HandleIdleSinceLastTransmission(false);
-}
-
-void MetricsService::HandleIdleSinceLastTransmission(bool in_idle) {
-  // If there wasn't a lot of action, maybe the computer was asleep, in which
-  // case, the log transmissions should have stopped.  Here we start them up
-  // again.
-  if (!in_idle && idle_since_last_transmission_)
-    StartSchedulerIfNecessary();
-  idle_since_last_transmission_ = in_idle;
-}
-
-void MetricsService::RecordStartOfSessionEnd() {
-  LogCleanShutdown();
-  RecordBooleanPrefValue(prefs::kStabilitySessionEndCompleted, false);
-}
-
-void MetricsService::RecordCompletedSessionEnd() {
-  LogCleanShutdown();
-  RecordBooleanPrefValue(prefs::kStabilitySessionEndCompleted, true);
-}
-
-#if defined(OS_ANDROID) || defined(OS_IOS)
-void MetricsService::OnAppEnterBackground() {
-  scheduler_->Stop();
-
-  MarkAppCleanShutdownAndCommit();
-
-  // At this point, there's no way of knowing when the process will be
-  // killed, so this has to be treated similar to a shutdown, closing and
-  // persisting all logs. Unlinke a shutdown, the state is primed to be ready
-  // to continue logging and uploading if the process does return.
-  if (recording_active() && state_ >= SENDING_INITIAL_STABILITY_LOG) {
-    PushPendingLogsToPersistentStorage();
-    // Persisting logs closes the current log, so start recording a new log
-    // immediately to capture any background work that might be done before the
-    // process is killed.
-    OpenNewLog();
-  }
-}
-
-void MetricsService::OnAppEnterForeground() {
-  PrefService* pref = g_browser_process->local_state();
-  pref->SetBoolean(prefs::kStabilityExitedCleanly, false);
-
-  StartSchedulerIfNecessary();
-}
-#else
-void MetricsService::LogNeedForCleanShutdown() {
-  PrefService* pref = g_browser_process->local_state();
-  pref->SetBoolean(prefs::kStabilityExitedCleanly, false);
-  // Redundant setting to be sure we call for a clean shutdown.
-  clean_shutdown_status_ = NEED_TO_SHUTDOWN;
-}
-#endif  // defined(OS_ANDROID) || defined(OS_IOS)
-
-// static
-void MetricsService::SetExecutionPhase(ExecutionPhase execution_phase) {
-  execution_phase_ = execution_phase;
-  PrefService* pref = g_browser_process->local_state();
-  pref->SetInteger(prefs::kStabilityExecutionPhase, execution_phase_);
-}
-
-void MetricsService::RecordBreakpadRegistration(bool success) {
-  if (!success)
-    IncrementPrefValue(prefs::kStabilityBreakpadRegistrationFail);
-  else
-    IncrementPrefValue(prefs::kStabilityBreakpadRegistrationSuccess);
-}
-
-void MetricsService::RecordBreakpadHasDebugger(bool has_debugger) {
-  if (!has_debugger)
-    IncrementPrefValue(prefs::kStabilityDebuggerNotPresent);
-  else
-    IncrementPrefValue(prefs::kStabilityDebuggerPresent);
-}
-
-#if defined(OS_WIN)
-void MetricsService::CountBrowserCrashDumpAttempts() {
-  // Open the registry key for iteration.
-  base::win::RegKey regkey;
-  if (regkey.Open(HKEY_CURRENT_USER,
-                  chrome::kBrowserCrashDumpAttemptsRegistryPath,
-                  KEY_ALL_ACCESS) != ERROR_SUCCESS) {
-    return;
-  }
-
-  // The values we're interested in counting are all prefixed with the version.
-  base::string16 chrome_version(base::ASCIIToUTF16(chrome::kChromeVersion));
-
-  // Track a list of values to delete. We don't modify the registry key while
-  // we're iterating over its values.
-  typedef std::vector<base::string16> StringVector;
-  StringVector to_delete;
-
-  // Iterate over the values in the key counting dumps with and without crashes.
-  // We directly walk the values instead of using RegistryValueIterator in order
-  // to read all of the values as DWORDS instead of strings.
-  base::string16 name;
-  DWORD value = 0;
-  int dumps_with_crash = 0;
-  int dumps_with_no_crash = 0;
-  for (int i = regkey.GetValueCount() - 1; i >= 0; --i) {
-    if (regkey.GetValueNameAt(i, &name) == ERROR_SUCCESS &&
-        StartsWith(name, chrome_version, false) &&
-        regkey.ReadValueDW(name.c_str(), &value) == ERROR_SUCCESS) {
-      to_delete.push_back(name);
-      if (value == 0)
-        ++dumps_with_no_crash;
-      else
-        ++dumps_with_crash;
-    }
-  }
-
-  // Delete the registry keys we've just counted.
-  for (StringVector::iterator i = to_delete.begin(); i != to_delete.end(); ++i)
-    regkey.DeleteValue(i->c_str());
-
-  // Capture the histogram samples.
-  if (dumps_with_crash != 0)
-    UMA_HISTOGRAM_COUNTS("Chrome.BrowserDumpsWithCrash", dumps_with_crash);
-  if (dumps_with_no_crash != 0)
-    UMA_HISTOGRAM_COUNTS("Chrome.BrowserDumpsWithNoCrash", dumps_with_no_crash);
-  int total_dumps = dumps_with_crash + dumps_with_no_crash;
-  if (total_dumps != 0)
-    UMA_HISTOGRAM_COUNTS("Chrome.BrowserCrashDumpAttempts", total_dumps);
-}
-#endif  // defined(OS_WIN)
-
-//------------------------------------------------------------------------------
-// private methods
-//------------------------------------------------------------------------------
-
-
-//------------------------------------------------------------------------------
-// Initialization methods
-
-void MetricsService::InitializeMetricsState(ReportingState reporting_state) {
-#if defined(OS_POSIX)
-  network_stats_server_ = chrome_common_net::kEchoTestServerLocation;
-  http_pipelining_test_server_ = chrome_common_net::kPipelineTestServerBaseUrl;
-#else
-  BrowserDistribution* dist = BrowserDistribution::GetDistribution();
-  network_stats_server_ = dist->GetNetworkStatsServer();
-  http_pipelining_test_server_ = dist->GetHttpPipeliningTestServer();
-#endif
-
-  PrefService* pref = g_browser_process->local_state();
-  DCHECK(pref);
-
-  pref->SetString(prefs::kStabilityStatsVersion,
-                  MetricsLog::GetVersionString());
-  pref->SetInt64(prefs::kStabilityStatsBuildTime, MetricsLog::GetBuildTime());
-
-  session_id_ = pref->GetInteger(prefs::kMetricsSessionID);
-
-#if defined(OS_ANDROID)
-  LogAndroidStabilityToPrefs(pref);
-#endif  // defined(OS_ANDROID)
-
-  if (!pref->GetBoolean(prefs::kStabilityExitedCleanly)) {
-    IncrementPrefValue(prefs::kStabilityCrashCount);
-    // Reset flag, and wait until we call LogNeedForCleanShutdown() before
-    // monitoring.
-    pref->SetBoolean(prefs::kStabilityExitedCleanly, true);
-
-    // TODO(rtenneti): On windows, consider saving/getting execution_phase from
-    // the registry.
-    int execution_phase = pref->GetInteger(prefs::kStabilityExecutionPhase);
-    UMA_HISTOGRAM_SPARSE_SLOWLY("Chrome.Browser.CrashedExecutionPhase",
-                                execution_phase);
-
-    // If the previous session didn't exit cleanly, then prepare an initial
-    // stability log if UMA is enabled.
-    if (reporting_state == REPORTING_ENABLED)
-      PrepareInitialStabilityLog();
-  }
-
-  // Update session ID.
-  ++session_id_;
-  pref->SetInteger(prefs::kMetricsSessionID, session_id_);
-
-  // Stability bookkeeping
-  IncrementPrefValue(prefs::kStabilityLaunchCount);
-
-  DCHECK_EQ(UNINITIALIZED_PHASE, execution_phase_);
-  SetExecutionPhase(START_METRICS_RECORDING);
-
-#if defined(OS_WIN)
-  CountBrowserCrashDumpAttempts();
-#endif  // defined(OS_WIN)
-
-  if (!pref->GetBoolean(prefs::kStabilitySessionEndCompleted)) {
-    IncrementPrefValue(prefs::kStabilityIncompleteSessionEndCount);
-    // This is marked false when we get a WM_ENDSESSION.
-    pref->SetBoolean(prefs::kStabilitySessionEndCompleted, true);
-  }
-
-  // Call GetUptimes() for the first time, thus allowing all later calls
-  // to record incremental uptimes accurately.
-  base::TimeDelta ignored_uptime_parameter;
-  base::TimeDelta startup_uptime;
-  GetUptimes(pref, &startup_uptime, &ignored_uptime_parameter);
-  DCHECK_EQ(0, startup_uptime.InMicroseconds());
-  // For backwards compatibility, leave this intact in case Omaha is checking
-  // them.  prefs::kStabilityLastTimestampSec may also be useless now.
-  // TODO(jar): Delete these if they have no uses.
-  pref->SetInt64(prefs::kStabilityLaunchTimeSec, Time::Now().ToTimeT());
-
-  // Bookkeeping for the uninstall metrics.
-  IncrementLongPrefsValue(prefs::kUninstallLaunchCount);
-
-  // Get stats on use of command line.
-  const CommandLine* command_line(CommandLine::ForCurrentProcess());
-  size_t common_commands = 0;
-  if (command_line->HasSwitch(switches::kUserDataDir)) {
-    ++common_commands;
-    UMA_HISTOGRAM_COUNTS_100("Chrome.CommandLineDatDirCount", 1);
-  }
-
-  if (command_line->HasSwitch(switches::kApp)) {
-    ++common_commands;
-    UMA_HISTOGRAM_COUNTS_100("Chrome.CommandLineAppModeCount", 1);
-  }
-
-  size_t switch_count = command_line->GetSwitches().size();
-  UMA_HISTOGRAM_COUNTS_100("Chrome.CommandLineFlagCount", switch_count);
-  UMA_HISTOGRAM_COUNTS_100("Chrome.CommandLineUncommonFlagCount",
-                           switch_count - common_commands);
-
-  // Kick off the process of saving the state (so the uptime numbers keep
-  // getting updated) every n minutes.
-  ScheduleNextStateSave();
-}
-
-// static
-void MetricsService::InitTaskGetHardwareClass(
-    base::WeakPtr<MetricsService> self,
-    base::MessageLoopProxy* target_loop) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
-
-  std::string hardware_class;
-#if defined(OS_CHROMEOS)
-  chromeos::system::StatisticsProvider::GetInstance()->GetMachineStatistic(
-      "hardware_class", &hardware_class);
-#endif  // OS_CHROMEOS
-
-  target_loop->PostTask(FROM_HERE,
-      base::Bind(&MetricsService::OnInitTaskGotHardwareClass,
-          self, hardware_class));
-}
-
-void MetricsService::OnInitTaskGotHardwareClass(
-    const std::string& hardware_class) {
-  DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
-  hardware_class_ = hardware_class;
-
-#if defined(ENABLE_PLUGINS)
-  // Start the next part of the init task: loading plugin information.
-  PluginService::GetInstance()->GetPlugins(
-      base::Bind(&MetricsService::OnInitTaskGotPluginInfo,
-          self_ptr_factory_.GetWeakPtr()));
-#else
-  std::vector<content::WebPluginInfo> plugin_list_empty;
-  OnInitTaskGotPluginInfo(plugin_list_empty);
-#endif  // defined(ENABLE_PLUGINS)
-}
-
-void MetricsService::OnInitTaskGotPluginInfo(
-    const std::vector<content::WebPluginInfo>& plugins) {
-  DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
-  plugins_ = plugins;
-
-  // Schedules a task on a blocking pool thread to gather Google Update
-  // statistics (requires Registry reads).
-  BrowserThread::PostBlockingPoolTask(
-      FROM_HERE,
-      base::Bind(&MetricsService::InitTaskGetGoogleUpdateData,
-                 self_ptr_factory_.GetWeakPtr(),
-                 base::MessageLoop::current()->message_loop_proxy()));
-}
-
-// static
-void MetricsService::InitTaskGetGoogleUpdateData(
-    base::WeakPtr<MetricsService> self,
-    base::MessageLoopProxy* target_loop) {
-  GoogleUpdateMetrics google_update_metrics;
-
-#if defined(OS_WIN) && defined(GOOGLE_CHROME_BUILD)
-  const bool system_install = GoogleUpdateSettings::IsSystemInstall();
-
-  google_update_metrics.is_system_install = system_install;
-  google_update_metrics.last_started_au =
-      GoogleUpdateSettings::GetGoogleUpdateLastStartedAU(system_install);
-  google_update_metrics.last_checked =
-      GoogleUpdateSettings::GetGoogleUpdateLastChecked(system_install);
-  GoogleUpdateSettings::GetUpdateDetailForGoogleUpdate(
-      system_install,
-      &google_update_metrics.google_update_data);
-  GoogleUpdateSettings::GetUpdateDetail(
-      system_install,
-      &google_update_metrics.product_data);
-#endif  // defined(OS_WIN) && defined(GOOGLE_CHROME_BUILD)
-
-  target_loop->PostTask(FROM_HERE,
-      base::Bind(&MetricsService::OnInitTaskGotGoogleUpdateData,
-          self, google_update_metrics));
-}
-
-void MetricsService::OnInitTaskGotGoogleUpdateData(
-    const GoogleUpdateMetrics& google_update_metrics) {
-  DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
-
-  google_update_metrics_ = google_update_metrics;
-
-  // Start the next part of the init task: fetching performance data.  This will
-  // call into |FinishedReceivingProfilerData()| when the task completes.
-  chrome_browser_metrics::TrackingSynchronizer::FetchProfilerDataAsynchronously(
-      self_ptr_factory_.GetWeakPtr());
-}
-
-void MetricsService::OnUserAction(const std::string& action) {
-  if (!ShouldLogEvents())
-    return;
-
-  log_manager_.current_log()->RecordUserAction(action);
-  HandleIdleSinceLastTransmission(false);
-}
-
-void MetricsService::ReceivedProfilerData(
-    const tracked_objects::ProcessDataSnapshot& process_data,
-    int process_type) {
-  DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
-
-  // Upon the first callback, create the initial log so that we can immediately
-  // save the profiler data.
-  if (!initial_metrics_log_.get()) {
-    initial_metrics_log_.reset(
-        new MetricsLog(client_id_, session_id_, MetricsLog::ONGOING_LOG));
-  }
-
-  initial_metrics_log_->RecordProfilerData(process_data, process_type);
-}
-
-void MetricsService::FinishedReceivingProfilerData() {
-  DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
-  state_ = INIT_TASK_DONE;
-  scheduler_->InitTaskComplete();
-}
-
-void MetricsService::GetUptimes(PrefService* pref,
-                                base::TimeDelta* incremental_uptime,
-                                base::TimeDelta* uptime) {
-  base::TimeTicks now = base::TimeTicks::Now();
-  // If this is the first call, init |first_updated_time_| and
-  // |last_updated_time_|.
-  if (last_updated_time_.is_null()) {
-    first_updated_time_ = now;
-    last_updated_time_ = now;
-  }
-  *incremental_uptime = now - last_updated_time_;
-  *uptime = now - first_updated_time_;
-  last_updated_time_ = now;
-
-  const int64 incremental_time_secs = incremental_uptime->InSeconds();
-  if (incremental_time_secs > 0) {
-    int64 metrics_uptime = pref->GetInt64(prefs::kUninstallMetricsUptimeSec);
-    metrics_uptime += incremental_time_secs;
-    pref->SetInt64(prefs::kUninstallMetricsUptimeSec, metrics_uptime);
-  }
-}
-
-void MetricsService::ResetMetricsIDsIfNecessary() {
-  if (metrics_ids_reset_check_performed_)
-    return;
-
-  metrics_ids_reset_check_performed_ = true;
-
-  PrefService* local_state = g_browser_process->local_state();
-  if (!local_state->GetBoolean(prefs::kMetricsResetIds))
-    return;
-
-  UMA_HISTOGRAM_BOOLEAN("UMA.MetricsIDsReset", true);
-
-  DCHECK(client_id_.empty());
-  DCHECK_EQ(kLowEntropySourceNotSet, low_entropy_source_);
-
-  local_state->ClearPref(prefs::kMetricsClientID);
-  local_state->ClearPref(prefs::kMetricsLowEntropySource);
-  local_state->ClearPref(prefs::kMetricsResetIds);
-}
-
-int MetricsService::GetLowEntropySource() {
+int MetricsStateManager::GetLowEntropySource() {
   // Note that the default value for the low entropy source and the default pref
   // value are both kLowEntropySourceNotSet, which is used to identify if the
   // value has been set or not.
   if (low_entropy_source_ != kLowEntropySourceNotSet)
     return low_entropy_source_;
 
-  ResetMetricsIDsIfNecessary();
-
-  PrefService* local_state = g_browser_process->local_state();
   const CommandLine* command_line(CommandLine::ForCurrentProcess());
   // Only try to load the value from prefs if the user did not request a reset.
   // Otherwise, skip to generating a new value.
   if (!command_line->HasSwitch(switches::kResetVariationState)) {
-    int value = local_state->GetInteger(prefs::kMetricsLowEntropySource);
+    int value = local_state_->GetInteger(prefs::kMetricsLowEntropySource);
     // If the value is outside the [0, kMaxLowEntropySize) range, re-generate
     // it below.
     if (value >= 0 && value < kMaxLowEntropySize) {
@@ -1198,886 +186,26 @@
 
   UMA_HISTOGRAM_BOOLEAN("UMA.GeneratedLowEntropySource", true);
   low_entropy_source_ = GenerateLowEntropySource();
-  local_state->SetInteger(prefs::kMetricsLowEntropySource, low_entropy_source_);
-  local_state->ClearPref(prefs::kMetricsOldLowEntropySource);
-  metrics::CachingPermutedEntropyProvider::ClearCache(local_state);
+  local_state_->SetInteger(prefs::kMetricsLowEntropySource,
+                           low_entropy_source_);
+  local_state_->ClearPref(prefs::kMetricsOldLowEntropySource);
+  metrics::CachingPermutedEntropyProvider::ClearCache(local_state_);
 
   return low_entropy_source_;
 }
 
-// static
-std::string MetricsService::GenerateClientID() {
-  return base::GenerateGUID();
-}
-
-//------------------------------------------------------------------------------
-// State save methods
-
-void MetricsService::ScheduleNextStateSave() {
-  state_saver_factory_.InvalidateWeakPtrs();
-
-  base::MessageLoop::current()->PostDelayedTask(FROM_HERE,
-      base::Bind(&MetricsService::SaveLocalState,
-                 state_saver_factory_.GetWeakPtr()),
-      base::TimeDelta::FromMinutes(kSaveStateIntervalMinutes));
-}
-
-void MetricsService::SaveLocalState() {
-  PrefService* pref = g_browser_process->local_state();
-  if (!pref) {
-    NOTREACHED();
+void MetricsStateManager::ResetMetricsIDsIfNecessary() {
+  if (!local_state_->GetBoolean(prefs::kMetricsResetIds))
     return;
-  }
 
-  RecordCurrentState(pref);
+  UMA_HISTOGRAM_BOOLEAN("UMA.MetricsIDsReset", true);
 
-  // TODO(jar):110021 Does this run down the batteries????
-  ScheduleNextStateSave();
-}
+  DCHECK(client_id_.empty());
+  DCHECK_EQ(kLowEntropySourceNotSet, low_entropy_source_);
 
-
-//------------------------------------------------------------------------------
-// Recording control methods
-
-void MetricsService::OpenNewLog() {
-  DCHECK(!log_manager_.current_log());
-
-  log_manager_.BeginLoggingWithLog(
-      new MetricsLog(client_id_, session_id_, MetricsLog::ONGOING_LOG));
-  if (state_ == INITIALIZED) {
-    // We only need to schedule that run once.
-    state_ = INIT_TASK_SCHEDULED;
-
-    // Schedules a task on the file thread for execution of slower
-    // initialization steps (such as plugin list generation) necessary
-    // for sending the initial log.  This avoids blocking the main UI
-    // thread.
-    BrowserThread::PostDelayedTask(
-        BrowserThread::FILE,
-        FROM_HERE,
-        base::Bind(&MetricsService::InitTaskGetHardwareClass,
-            self_ptr_factory_.GetWeakPtr(),
-            base::MessageLoop::current()->message_loop_proxy()),
-        base::TimeDelta::FromSeconds(kInitializationDelaySeconds));
-  }
+  local_state_->ClearPref(prefs::kMetricsClientID);
+  local_state_->ClearPref(prefs::kMetricsLowEntropySource);
+  local_state_->ClearPref(prefs::kMetricsResetIds);
 }
 
-void MetricsService::CloseCurrentLog() {
-  if (!log_manager_.current_log())
-    return;
-
-  // TODO(jar): Integrate bounds on log recording more consistently, so that we
-  // can stop recording logs that are too big much sooner.
-  if (log_manager_.current_log()->num_events() > kEventLimit) {
-    UMA_HISTOGRAM_COUNTS("UMA.Discarded Log Events",
-                         log_manager_.current_log()->num_events());
-    log_manager_.DiscardCurrentLog();
-    OpenNewLog();  // Start trivial log to hold our histograms.
-  }
-
-  // Adds to ongoing logs.
-  log_manager_.current_log()->set_hardware_class(hardware_class_);
-
-  // Put incremental data (histogram deltas, and realtime stats deltas) at the
-  // end of all log transmissions (initial log handles this separately).
-  // RecordIncrementalStabilityElements only exists on the derived
-  // MetricsLog class.
-  MetricsLog* current_log =
-      static_cast<MetricsLog*>(log_manager_.current_log());
-  DCHECK(current_log);
-  std::vector<chrome_variations::ActiveGroupId> synthetic_trials;
-  GetCurrentSyntheticFieldTrials(&synthetic_trials);
-  current_log->RecordEnvironment(plugins_, google_update_metrics_,
-                                 synthetic_trials);
-  PrefService* pref = g_browser_process->local_state();
-  base::TimeDelta incremental_uptime;
-  base::TimeDelta uptime;
-  GetUptimes(pref, &incremental_uptime, &uptime);
-  current_log->RecordStabilityMetrics(incremental_uptime, uptime);
-
-  RecordCurrentHistograms();
-
-  log_manager_.FinishCurrentLog();
-}
-
-void MetricsService::PushPendingLogsToPersistentStorage() {
-  if (state_ < SENDING_INITIAL_STABILITY_LOG)
-    return;  // We didn't and still don't have time to get plugin list etc.
-
-  if (log_manager_.has_staged_log()) {
-    // We may race here, and send second copy of the log later.
-    MetricsLogManager::StoreType store_type;
-    if (current_fetch_.get())
-      store_type = MetricsLogManager::PROVISIONAL_STORE;
-    else
-      store_type = MetricsLogManager::NORMAL_STORE;
-    log_manager_.StoreStagedLogAsUnsent(store_type);
-  }
-  DCHECK(!log_manager_.has_staged_log());
-  CloseCurrentLog();
-  log_manager_.PersistUnsentLogs();
-
-  // If there was a staged and/or current log, then there is now at least one
-  // log waiting to be uploaded.
-  if (log_manager_.has_unsent_logs())
-    state_ = SENDING_OLD_LOGS;
-}
-
-//------------------------------------------------------------------------------
-// Transmission of logs methods
-
-void MetricsService::StartSchedulerIfNecessary() {
-  // Never schedule cutting or uploading of logs in test mode.
-  if (test_mode_active_)
-    return;
-
-  // Even if reporting is disabled, the scheduler is needed to trigger the
-  // creation of the initial log, which must be done in order for any logs to be
-  // persisted on shutdown or backgrounding.
-  if (recording_active() &&
-      (reporting_active() || state_ < SENDING_INITIAL_STABILITY_LOG)) {
-    scheduler_->Start();
-  }
-}
-
-void MetricsService::StartScheduledUpload() {
-  // If we're getting no notifications, then the log won't have much in it, and
-  // it's possible the computer is about to go to sleep, so don't upload and
-  // stop the scheduler.
-  // If recording has been turned off, the scheduler doesn't need to run.
-  // If reporting is off, proceed if the initial log hasn't been created, since
-  // that has to happen in order for logs to be cut and stored when persisting.
-  // TODO(stuartmorgan): Call Stop() on the schedule when reporting and/or
-  // recording are turned off instead of letting it fire and then aborting.
-  if (idle_since_last_transmission_ ||
-      !recording_active() ||
-      (!reporting_active() && state_ >= SENDING_INITIAL_STABILITY_LOG)) {
-    scheduler_->Stop();
-    scheduler_->UploadCancelled();
-    return;
-  }
-
-  // If the callback was to upload an old log, but there no longer is one,
-  // just report success back to the scheduler to begin the ongoing log
-  // callbacks.
-  // TODO(stuartmorgan): Consider removing the distinction between
-  // SENDING_OLD_LOGS and SENDING_CURRENT_LOGS to simplify the state machine
-  // now that the log upload flow is the same for both modes.
-  if (state_ == SENDING_OLD_LOGS && !log_manager_.has_unsent_logs()) {
-    state_ = SENDING_CURRENT_LOGS;
-    scheduler_->UploadFinished(true /* healthy */, false /* no unsent logs */);
-    return;
-  }
-  // If there are unsent logs, send the next one. If not, start the asynchronous
-  // process of finalizing the current log for upload.
-  if (state_ == SENDING_OLD_LOGS) {
-    DCHECK(log_manager_.has_unsent_logs());
-    log_manager_.StageNextLogForUpload();
-    SendStagedLog();
-  } else {
-    StartFinalLogInfoCollection();
-  }
-}
-
-void MetricsService::StartFinalLogInfoCollection() {
-  // Begin the multi-step process of collecting memory usage histograms:
-  // First spawn a task to collect the memory details; when that task is
-  // finished, it will call OnMemoryDetailCollectionDone. That will in turn
-  // call HistogramSynchronization to collect histograms from all renderers and
-  // then call OnHistogramSynchronizationDone to continue processing.
-  DCHECK(!waiting_for_asynchronous_reporting_step_);
-  waiting_for_asynchronous_reporting_step_ = true;
-
-  base::Closure callback =
-      base::Bind(&MetricsService::OnMemoryDetailCollectionDone,
-                 self_ptr_factory_.GetWeakPtr());
-
-  scoped_refptr<MetricsMemoryDetails> details(
-      new MetricsMemoryDetails(callback));
-  details->StartFetch(MemoryDetails::UPDATE_USER_METRICS);
-
-  // Collect WebCore cache information to put into a histogram.
-  for (content::RenderProcessHost::iterator i(
-          content::RenderProcessHost::AllHostsIterator());
-       !i.IsAtEnd(); i.Advance())
-    i.GetCurrentValue()->Send(new ChromeViewMsg_GetCacheResourceStats());
-}
-
-void MetricsService::OnMemoryDetailCollectionDone() {
-  DCHECK(IsSingleThreaded());
-  // This function should only be called as the callback from an ansynchronous
-  // step.
-  DCHECK(waiting_for_asynchronous_reporting_step_);
-
-  // Create a callback_task for OnHistogramSynchronizationDone.
-  base::Closure callback = base::Bind(
-      &MetricsService::OnHistogramSynchronizationDone,
-      self_ptr_factory_.GetWeakPtr());
-
-  base::TimeDelta timeout =
-      base::TimeDelta::FromMilliseconds(kMaxHistogramGatheringWaitDuration);
-
-  DCHECK_EQ(num_async_histogram_fetches_in_progress_, 0);
-
-#if defined(OS_ANDROID)
-  // Android has no service process.
-  num_async_histogram_fetches_in_progress_ = 1;
-#else  // OS_ANDROID
-  num_async_histogram_fetches_in_progress_ = 2;
-  // Run requests to service and content in parallel.
-  if (!ServiceProcessControl::GetInstance()->GetHistograms(callback, timeout)) {
-    // Assume |num_async_histogram_fetches_in_progress_| is not changed by
-    // |GetHistograms()|.
-    DCHECK_EQ(num_async_histogram_fetches_in_progress_, 2);
-    // Assign |num_async_histogram_fetches_in_progress_| above and decrement it
-    // here to make code work even if |GetHistograms()| fired |callback|.
-    --num_async_histogram_fetches_in_progress_;
-  }
-#endif  // OS_ANDROID
-
-  // Set up the callback to task to call after we receive histograms from all
-  // child processes. Wait time specifies how long to wait before absolutely
-  // calling us back on the task.
-  content::FetchHistogramsAsynchronously(base::MessageLoop::current(), callback,
-                                         timeout);
-}
-
-void MetricsService::OnHistogramSynchronizationDone() {
-  DCHECK(IsSingleThreaded());
-  // This function should only be called as the callback from an ansynchronous
-  // step.
-  DCHECK(waiting_for_asynchronous_reporting_step_);
-  DCHECK_GT(num_async_histogram_fetches_in_progress_, 0);
-
-  // Check if all expected requests finished.
-  if (--num_async_histogram_fetches_in_progress_ > 0)
-    return;
-
-  waiting_for_asynchronous_reporting_step_ = false;
-  OnFinalLogInfoCollectionDone();
-}
-
-void MetricsService::OnFinalLogInfoCollectionDone() {
-  // If somehow there is a fetch in progress, we return and hope things work
-  // out. The scheduler isn't informed since if this happens, the scheduler
-  // will get a response from the upload.
-  DCHECK(!current_fetch_.get());
-  if (current_fetch_.get())
-    return;
-
-  // Abort if metrics were turned off during the final info gathering.
-  if (!recording_active()) {
-    scheduler_->Stop();
-    scheduler_->UploadCancelled();
-    return;
-  }
-
-  StageNewLog();
-
-  // If logs shouldn't be uploaded, stop here. It's important that this check
-  // be after StageNewLog(), otherwise the previous logs will never be loaded,
-  // and thus the open log won't be persisted.
-  // TODO(stuartmorgan): This is unnecessarily complicated; restructure loading
-  // of previous logs to not require running part of the upload logic.
-  // http://crbug.com/157337
-  if (!reporting_active()) {
-    scheduler_->Stop();
-    scheduler_->UploadCancelled();
-    return;
-  }
-
-  SendStagedLog();
-}
-
-void MetricsService::StageNewLog() {
-  if (log_manager_.has_staged_log())
-    return;
-
-  switch (state_) {
-    case INITIALIZED:
-    case INIT_TASK_SCHEDULED:  // We should be further along by now.
-      NOTREACHED();
-      return;
-
-    case INIT_TASK_DONE:
-      if (has_initial_stability_log_) {
-        // There's an initial stability log, ready to send.
-        log_manager_.StageNextLogForUpload();
-        has_initial_stability_log_ = false;
-        // Note: No need to call LoadPersistedUnsentLogs() here because unsent
-        // logs have already been loaded by PrepareInitialStabilityLog().
-        state_ = SENDING_INITIAL_STABILITY_LOG;
-      } else {
-        PrepareInitialMetricsLog();
-        // Load unsent logs (if any) from local state.
-        log_manager_.LoadPersistedUnsentLogs();
-        state_ = SENDING_INITIAL_METRICS_LOG;
-      }
-      break;
-
-    case SENDING_OLD_LOGS:
-      NOTREACHED();  // Shouldn't be staging a new log during old log sending.
-      return;
-
-    case SENDING_CURRENT_LOGS:
-      CloseCurrentLog();
-      OpenNewLog();
-      log_manager_.StageNextLogForUpload();
-      break;
-
-    default:
-      NOTREACHED();
-      return;
-  }
-
-  DCHECK(log_manager_.has_staged_log());
-}
-
-void MetricsService::PrepareInitialStabilityLog() {
-  DCHECK_EQ(INITIALIZED, state_);
-  PrefService* pref = g_browser_process->local_state();
-  DCHECK_NE(0, pref->GetInteger(prefs::kStabilityCrashCount));
-
-  scoped_ptr<MetricsLog> initial_stability_log(
-      new MetricsLog(client_id_, session_id_,
-                     MetricsLog::INITIAL_STABILITY_LOG));
-  if (!initial_stability_log->LoadSavedEnvironmentFromPrefs())
-    return;
-  initial_stability_log->RecordStabilityMetrics(base::TimeDelta(),
-                                                base::TimeDelta());
-  log_manager_.LoadPersistedUnsentLogs();
-
-  log_manager_.PauseCurrentLog();
-  log_manager_.BeginLoggingWithLog(initial_stability_log.release());
-#if defined(OS_ANDROID)
-  ConvertAndroidStabilityPrefsToHistograms(pref);
-  RecordCurrentStabilityHistograms();
-#endif  // defined(OS_ANDROID)
-  log_manager_.FinishCurrentLog();
-  log_manager_.ResumePausedLog();
-
-  // Store unsent logs, including the stability log that was just saved, so
-  // that they're not lost in case of a crash before upload time.
-  log_manager_.PersistUnsentLogs();
-
-  has_initial_stability_log_ = true;
-}
-
-void MetricsService::PrepareInitialMetricsLog() {
-  DCHECK(state_ == INIT_TASK_DONE || state_ == SENDING_INITIAL_STABILITY_LOG);
-  initial_metrics_log_->set_hardware_class(hardware_class_);
-
-  std::vector<chrome_variations::ActiveGroupId> synthetic_trials;
-  GetCurrentSyntheticFieldTrials(&synthetic_trials);
-  initial_metrics_log_->RecordEnvironment(plugins_, google_update_metrics_,
-                                          synthetic_trials);
-  PrefService* pref = g_browser_process->local_state();
-  base::TimeDelta incremental_uptime;
-  base::TimeDelta uptime;
-  GetUptimes(pref, &incremental_uptime, &uptime);
-  initial_metrics_log_->RecordStabilityMetrics(incremental_uptime, uptime);
-
-  // Histograms only get written to the current log, so make the new log current
-  // before writing them.
-  log_manager_.PauseCurrentLog();
-  log_manager_.BeginLoggingWithLog(initial_metrics_log_.release());
-#if defined(OS_ANDROID)
-  ConvertAndroidStabilityPrefsToHistograms(pref);
-#endif  // defined(OS_ANDROID)
-  RecordCurrentHistograms();
-  log_manager_.FinishCurrentLog();
-  log_manager_.ResumePausedLog();
-
-  DCHECK(!log_manager_.has_staged_log());
-  log_manager_.StageNextLogForUpload();
-}
-
-void MetricsService::SendStagedLog() {
-  DCHECK(log_manager_.has_staged_log());
-
-  PrepareFetchWithStagedLog();
-
-  bool upload_created = (current_fetch_.get() != NULL);
-  UMA_HISTOGRAM_BOOLEAN("UMA.UploadCreation", upload_created);
-  if (!upload_created) {
-    // Compression failed, and log discarded :-/.
-    // Skip this upload and hope things work out next time.
-    log_manager_.DiscardStagedLog();
-    scheduler_->UploadCancelled();
-    return;
-  }
-
-  DCHECK(!waiting_for_asynchronous_reporting_step_);
-  waiting_for_asynchronous_reporting_step_ = true;
-
-  current_fetch_->Start();
-
-  HandleIdleSinceLastTransmission(true);
-}
-
-void MetricsService::PrepareFetchWithStagedLog() {
-  DCHECK(log_manager_.has_staged_log());
-
-  // Prepare the protobuf version.
-  DCHECK(!current_fetch_.get());
-  if (log_manager_.has_staged_log()) {
-    current_fetch_.reset(net::URLFetcher::Create(
-        GURL(kServerUrl), net::URLFetcher::POST, this));
-    current_fetch_->SetRequestContext(
-        g_browser_process->system_request_context());
-
-    std::string log_text = log_manager_.staged_log_text();
-    std::string compressed_log_text;
-    bool compression_successful = chrome::GzipCompress(log_text,
-                                                       &compressed_log_text);
-    DCHECK(compression_successful);
-    if (compression_successful) {
-      current_fetch_->SetUploadData(kMimeType, compressed_log_text);
-      // Tell the server that we're uploading gzipped protobufs.
-      current_fetch_->SetExtraRequestHeaders("content-encoding: gzip");
-      const std::string hash =
-          base::HexEncode(log_manager_.staged_log_hash().data(),
-                          log_manager_.staged_log_hash().size());
-      DCHECK(!hash.empty());
-      current_fetch_->AddExtraRequestHeader("X-Chrome-UMA-Log-SHA1: " + hash);
-      UMA_HISTOGRAM_PERCENTAGE(
-          "UMA.ProtoCompressionRatio",
-          100 * compressed_log_text.size() / log_text.size());
-      UMA_HISTOGRAM_CUSTOM_COUNTS(
-          "UMA.ProtoGzippedKBSaved",
-          (log_text.size() - compressed_log_text.size()) / 1024,
-          1, 2000, 50);
-    }
-
-    // We already drop cookies server-side, but we might as well strip them out
-    // client-side as well.
-    current_fetch_->SetLoadFlags(net::LOAD_DO_NOT_SAVE_COOKIES |
-                                 net::LOAD_DO_NOT_SEND_COOKIES);
-  }
-}
-
-void MetricsService::OnURLFetchComplete(const net::URLFetcher* source) {
-  DCHECK(waiting_for_asynchronous_reporting_step_);
-
-  // We're not allowed to re-use the existing |URLFetcher|s, so free them here.
-  // Note however that |source| is aliased to the fetcher, so we should be
-  // careful not to delete it too early.
-  DCHECK_EQ(current_fetch_.get(), source);
-  scoped_ptr<net::URLFetcher> s(current_fetch_.Pass());
-
-  int response_code = source->GetResponseCode();
-
-  // Log a histogram to track response success vs. failure rates.
-  UMA_HISTOGRAM_ENUMERATION("UMA.UploadResponseStatus.Protobuf",
-                            ResponseCodeToStatus(response_code),
-                            NUM_RESPONSE_STATUSES);
-
-  // If the upload was provisionally stored, drop it now that the upload is
-  // known to have gone through.
-  log_manager_.DiscardLastProvisionalStore();
-
-  bool upload_succeeded = response_code == 200;
-
-  // Provide boolean for error recovery (allow us to ignore response_code).
-  bool discard_log = false;
-  const size_t log_size = log_manager_.staged_log_text().length();
-  if (!upload_succeeded && log_size > kUploadLogAvoidRetransmitSize) {
-    UMA_HISTOGRAM_COUNTS("UMA.Large Rejected Log was Discarded",
-                         static_cast<int>(log_size));
-    discard_log = true;
-  } else if (response_code == 400) {
-    // Bad syntax.  Retransmission won't work.
-    discard_log = true;
-  }
-
-  if (upload_succeeded || discard_log)
-    log_manager_.DiscardStagedLog();
-
-  waiting_for_asynchronous_reporting_step_ = false;
-
-  if (!log_manager_.has_staged_log()) {
-    switch (state_) {
-      case SENDING_INITIAL_STABILITY_LOG:
-        // Store the updated list to disk now that the removed log is uploaded.
-        log_manager_.PersistUnsentLogs();
-        PrepareInitialMetricsLog();
-        SendStagedLog();
-        state_ = SENDING_INITIAL_METRICS_LOG;
-        break;
-
-      case SENDING_INITIAL_METRICS_LOG:
-        // The initial metrics log never gets persisted to local state, so it's
-        // not necessary to call log_manager_.PersistUnsentLogs() here.
-        // TODO(asvitkine): It should be persisted like the initial stability
-        // log and old unsent logs. http://crbug.com/328417
-        state_ = log_manager_.has_unsent_logs() ? SENDING_OLD_LOGS
-                                                : SENDING_CURRENT_LOGS;
-        break;
-
-      case SENDING_OLD_LOGS:
-        // Store the updated list to disk now that the removed log is uploaded.
-        log_manager_.PersistUnsentLogs();
-        if (!log_manager_.has_unsent_logs())
-          state_ = SENDING_CURRENT_LOGS;
-        break;
-
-      case SENDING_CURRENT_LOGS:
-        break;
-
-      default:
-        NOTREACHED();
-        break;
-    }
-
-    if (log_manager_.has_unsent_logs())
-      DCHECK_LT(state_, SENDING_CURRENT_LOGS);
-  }
-
-  // Error 400 indicates a problem with the log, not with the server, so
-  // don't consider that a sign that the server is in trouble.
-  bool server_is_healthy = upload_succeeded || response_code == 400;
-  // Don't notify the scheduler that the upload is finished if we've only sent
-  // the initial stability log, but not yet the initial metrics log (treat the
-  // two as a single unit of work as far as the scheduler is concerned).
-  if (state_ != SENDING_INITIAL_METRICS_LOG) {
-    scheduler_->UploadFinished(server_is_healthy,
-                               log_manager_.has_unsent_logs());
-  }
-
-  // Collect network stats if UMA upload succeeded.
-  IOThread* io_thread = g_browser_process->io_thread();
-  if (server_is_healthy && io_thread) {
-    chrome_browser_net::CollectNetworkStats(network_stats_server_, io_thread);
-    chrome_browser_net::CollectPipeliningCapabilityStatsOnUIThread(
-        http_pipelining_test_server_, io_thread);
-#if defined(OS_WIN)
-    chrome::CollectTimeTicksStats();
-#endif
-  }
-}
-
-void MetricsService::IncrementPrefValue(const char* path) {
-  PrefService* pref = g_browser_process->local_state();
-  DCHECK(pref);
-  int value = pref->GetInteger(path);
-  pref->SetInteger(path, value + 1);
-}
-
-void MetricsService::IncrementLongPrefsValue(const char* path) {
-  PrefService* pref = g_browser_process->local_state();
-  DCHECK(pref);
-  int64 value = pref->GetInt64(path);
-  pref->SetInt64(path, value + 1);
-}
-
-void MetricsService::LogLoadStarted(content::WebContents* web_contents) {
-  content::RecordAction(base::UserMetricsAction("PageLoad"));
-  HISTOGRAM_ENUMERATION("Chrome.UmaPageloadCounter", 1, 2);
-  IncrementPrefValue(prefs::kStabilityPageLoadCount);
-  IncrementLongPrefsValue(prefs::kUninstallMetricsPageLoadCount);
-  // We need to save the prefs, as page load count is a critical stat, and it
-  // might be lost due to a crash :-(.
-}
-
-void MetricsService::LogRendererCrash(content::RenderProcessHost* host,
-                                      base::TerminationStatus status,
-                                      int exit_code) {
-  bool was_extension_process =
-      extensions::ProcessMap::Get(host->GetBrowserContext())
-          ->Contains(host->GetID());
-  if (status == base::TERMINATION_STATUS_PROCESS_CRASHED ||
-      status == base::TERMINATION_STATUS_ABNORMAL_TERMINATION) {
-    if (was_extension_process) {
-      IncrementPrefValue(prefs::kStabilityExtensionRendererCrashCount);
-
-      UMA_HISTOGRAM_SPARSE_SLOWLY("CrashExitCodes.Extension",
-                                  MapCrashExitCodeForHistogram(exit_code));
-    } else {
-      IncrementPrefValue(prefs::kStabilityRendererCrashCount);
-
-      UMA_HISTOGRAM_SPARSE_SLOWLY("CrashExitCodes.Renderer",
-                                  MapCrashExitCodeForHistogram(exit_code));
-    }
-
-    UMA_HISTOGRAM_PERCENTAGE("BrowserRenderProcessHost.ChildCrashes",
-                             was_extension_process ? 2 : 1);
-  } else if (status == base::TERMINATION_STATUS_PROCESS_WAS_KILLED) {
-    UMA_HISTOGRAM_PERCENTAGE("BrowserRenderProcessHost.ChildKills",
-                             was_extension_process ? 2 : 1);
-  } else if (status == base::TERMINATION_STATUS_STILL_RUNNING) {
-    UMA_HISTOGRAM_PERCENTAGE("BrowserRenderProcessHost.DisconnectedAlive",
-                               was_extension_process ? 2 : 1);
-  }
-}
-
-void MetricsService::LogRendererHang() {
-  IncrementPrefValue(prefs::kStabilityRendererHangCount);
-}
-
-bool MetricsService::UmaMetricsProperlyShutdown() {
-  CHECK(clean_shutdown_status_ == CLEANLY_SHUTDOWN ||
-        clean_shutdown_status_ == NEED_TO_SHUTDOWN);
-  return clean_shutdown_status_ == CLEANLY_SHUTDOWN;
-}
-
-void MetricsService::RegisterSyntheticFieldTrial(
-    const SyntheticTrialGroup& trial) {
-  for (size_t i = 0; i < synthetic_trial_groups_.size(); ++i) {
-    if (synthetic_trial_groups_[i].id.name == trial.id.name) {
-      if (synthetic_trial_groups_[i].id.group != trial.id.group) {
-        synthetic_trial_groups_[i].id.group = trial.id.group;
-        synthetic_trial_groups_[i].start_time = base::TimeTicks::Now();
-      }
-      return;
-    }
-  }
-
-  SyntheticTrialGroup trial_group = trial;
-  trial_group.start_time = base::TimeTicks::Now();
-  synthetic_trial_groups_.push_back(trial_group);
-}
-
-void MetricsService::CheckForClonedInstall() {
-  DCHECK(!cloned_install_detector_);
-
-  metrics::MachineIdProvider* provider =
-      metrics::MachineIdProvider::CreateInstance();
-  if (!provider)
-    return;
-
-  cloned_install_detector_.reset(
-      new metrics::ClonedInstallDetector(provider));
-
-  PrefService* local_state = g_browser_process->local_state();
-  cloned_install_detector_->CheckForClonedInstall(local_state);
-}
-
-void MetricsService::GetCurrentSyntheticFieldTrials(
-    std::vector<chrome_variations::ActiveGroupId>* synthetic_trials) {
-  DCHECK(synthetic_trials);
-  synthetic_trials->clear();
-  const MetricsLog* current_log =
-      static_cast<const MetricsLog*>(log_manager_.current_log());
-  for (size_t i = 0; i < synthetic_trial_groups_.size(); ++i) {
-    if (synthetic_trial_groups_[i].start_time <= current_log->creation_time())
-      synthetic_trials->push_back(synthetic_trial_groups_[i].id);
-  }
-}
-
-void MetricsService::LogCleanShutdown() {
-  // Redundant hack to write pref ASAP.
-  MarkAppCleanShutdownAndCommit();
-
-  // Redundant setting to assure that we always reset this value at shutdown
-  // (and that we don't use some alternate path, and not call LogCleanShutdown).
-  clean_shutdown_status_ = CLEANLY_SHUTDOWN;
-
-  RecordBooleanPrefValue(prefs::kStabilityExitedCleanly, true);
-  PrefService* pref = g_browser_process->local_state();
-  pref->SetInteger(prefs::kStabilityExecutionPhase,
-                   MetricsService::SHUTDOWN_COMPLETE);
-}
-
-#if defined(OS_CHROMEOS)
-void MetricsService::LogChromeOSCrash(const std::string &crash_type) {
-  if (crash_type == "user")
-    IncrementPrefValue(prefs::kStabilityOtherUserCrashCount);
-  else if (crash_type == "kernel")
-    IncrementPrefValue(prefs::kStabilityKernelCrashCount);
-  else if (crash_type == "uncleanshutdown")
-    IncrementPrefValue(prefs::kStabilitySystemUncleanShutdownCount);
-  else
-    NOTREACHED() << "Unexpected Chrome OS crash type " << crash_type;
-  // Wake up metrics logs sending if necessary now that new
-  // log data is available.
-  HandleIdleSinceLastTransmission(false);
-}
-#endif  // OS_CHROMEOS
-
-void MetricsService::LogPluginLoadingError(const base::FilePath& plugin_path) {
-  content::WebPluginInfo plugin;
-  bool success =
-      content::PluginService::GetInstance()->GetPluginInfoByPath(plugin_path,
-                                                                 &plugin);
-  DCHECK(success);
-  ChildProcessStats& stats = child_process_stats_buffer_[plugin.name];
-  // Initialize the type if this entry is new.
-  if (stats.process_type == content::PROCESS_TYPE_UNKNOWN) {
-    // The plug-in process might not actually of type PLUGIN (which means
-    // NPAPI), but we only care that it is *a* plug-in process.
-    stats.process_type = content::PROCESS_TYPE_PLUGIN;
-  } else {
-    DCHECK(IsPluginProcess(stats.process_type));
-  }
-  stats.loading_errors++;
-}
-
-MetricsService::ChildProcessStats& MetricsService::GetChildProcessStats(
-    const content::ChildProcessData& data) {
-  const base::string16& child_name = data.name;
-  if (!ContainsKey(child_process_stats_buffer_, child_name)) {
-    child_process_stats_buffer_[child_name] =
-        ChildProcessStats(data.process_type);
-  }
-  return child_process_stats_buffer_[child_name];
-}
-
-void MetricsService::RecordPluginChanges(PrefService* pref) {
-  ListPrefUpdate update(pref, prefs::kStabilityPluginStats);
-  base::ListValue* plugins = update.Get();
-  DCHECK(plugins);
-
-  for (base::ListValue::iterator value_iter = plugins->begin();
-       value_iter != plugins->end(); ++value_iter) {
-    if (!(*value_iter)->IsType(base::Value::TYPE_DICTIONARY)) {
-      NOTREACHED();
-      continue;
-    }
-
-    base::DictionaryValue* plugin_dict =
-        static_cast<base::DictionaryValue*>(*value_iter);
-    std::string plugin_name;
-    plugin_dict->GetString(prefs::kStabilityPluginName, &plugin_name);
-    if (plugin_name.empty()) {
-      NOTREACHED();
-      continue;
-    }
-
-    // TODO(viettrungluu): remove conversions
-    base::string16 name16 = base::UTF8ToUTF16(plugin_name);
-    if (child_process_stats_buffer_.find(name16) ==
-        child_process_stats_buffer_.end()) {
-      continue;
-    }
-
-    ChildProcessStats stats = child_process_stats_buffer_[name16];
-    if (stats.process_launches) {
-      int launches = 0;
-      plugin_dict->GetInteger(prefs::kStabilityPluginLaunches, &launches);
-      launches += stats.process_launches;
-      plugin_dict->SetInteger(prefs::kStabilityPluginLaunches, launches);
-    }
-    if (stats.process_crashes) {
-      int crashes = 0;
-      plugin_dict->GetInteger(prefs::kStabilityPluginCrashes, &crashes);
-      crashes += stats.process_crashes;
-      plugin_dict->SetInteger(prefs::kStabilityPluginCrashes, crashes);
-    }
-    if (stats.instances) {
-      int instances = 0;
-      plugin_dict->GetInteger(prefs::kStabilityPluginInstances, &instances);
-      instances += stats.instances;
-      plugin_dict->SetInteger(prefs::kStabilityPluginInstances, instances);
-    }
-    if (stats.loading_errors) {
-      int loading_errors = 0;
-      plugin_dict->GetInteger(prefs::kStabilityPluginLoadingErrors,
-                              &loading_errors);
-      loading_errors += stats.loading_errors;
-      plugin_dict->SetInteger(prefs::kStabilityPluginLoadingErrors,
-                              loading_errors);
-    }
-
-    child_process_stats_buffer_.erase(name16);
-  }
-
-  // Now go through and add dictionaries for plugins that didn't already have
-  // reports in Local State.
-  for (std::map<base::string16, ChildProcessStats>::iterator cache_iter =
-           child_process_stats_buffer_.begin();
-       cache_iter != child_process_stats_buffer_.end(); ++cache_iter) {
-    ChildProcessStats stats = cache_iter->second;
-
-    // Insert only plugins information into the plugins list.
-    if (!IsPluginProcess(stats.process_type))
-      continue;
-
-    // TODO(viettrungluu): remove conversion
-    std::string plugin_name = base::UTF16ToUTF8(cache_iter->first);
-
-    base::DictionaryValue* plugin_dict = new base::DictionaryValue;
-
-    plugin_dict->SetString(prefs::kStabilityPluginName, plugin_name);
-    plugin_dict->SetInteger(prefs::kStabilityPluginLaunches,
-                            stats.process_launches);
-    plugin_dict->SetInteger(prefs::kStabilityPluginCrashes,
-                            stats.process_crashes);
-    plugin_dict->SetInteger(prefs::kStabilityPluginInstances,
-                            stats.instances);
-    plugin_dict->SetInteger(prefs::kStabilityPluginLoadingErrors,
-                            stats.loading_errors);
-    plugins->Append(plugin_dict);
-  }
-  child_process_stats_buffer_.clear();
-}
-
-bool MetricsService::ShouldLogEvents() {
-  // We simply don't log events to UMA if there is a single incognito
-  // session visible. The problem is that we always notify using the orginal
-  // profile in order to simplify notification processing.
-  return !chrome::IsOffTheRecordSessionActive();
-}
-
-void MetricsService::RecordBooleanPrefValue(const char* path, bool value) {
-  DCHECK(IsSingleThreaded());
-
-  PrefService* pref = g_browser_process->local_state();
-  DCHECK(pref);
-
-  pref->SetBoolean(path, value);
-  RecordCurrentState(pref);
-}
-
-void MetricsService::RecordCurrentState(PrefService* pref) {
-  pref->SetInt64(prefs::kStabilityLastTimestampSec, Time::Now().ToTimeT());
-
-  RecordPluginChanges(pref);
-}
-
-// static
-bool MetricsService::IsPluginProcess(int process_type) {
-  return (process_type == content::PROCESS_TYPE_PLUGIN ||
-          process_type == content::PROCESS_TYPE_PPAPI_PLUGIN ||
-          process_type == content::PROCESS_TYPE_PPAPI_BROKER);
-}
-
-#if defined(OS_CHROMEOS)
-void MetricsService::StartExternalMetrics() {
-  external_metrics_ = new chromeos::ExternalMetrics;
-  external_metrics_->Start();
-}
-#endif
-
-// static
-bool MetricsServiceHelper::IsMetricsReportingEnabled() {
-  bool result = false;
-  const PrefService* local_state = g_browser_process->local_state();
-  if (local_state) {
-    const PrefService::Preference* uma_pref =
-        local_state->FindPreference(prefs::kMetricsReportingEnabled);
-    if (uma_pref) {
-      bool success = uma_pref->GetValue()->GetAsBoolean(&result);
-      DCHECK(success);
-    }
-  }
-  return result;
-}
-
-bool MetricsServiceHelper::IsCrashReportingEnabled() {
-#if defined(GOOGLE_CHROME_BUILD)
-#if defined(OS_CHROMEOS)
-  bool reporting_enabled = false;
-  chromeos::CrosSettings::Get()->GetBoolean(chromeos::kStatsReportingPref,
-                                            &reporting_enabled);
-  return reporting_enabled;
-#elif defined(OS_ANDROID)
-  // Android has its own settings for metrics / crash uploading.
-  const PrefService* prefs = g_browser_process->local_state();
-  return prefs->GetBoolean(prefs::kCrashReportingEnabled);
-#else
-  return MetricsServiceHelper::IsMetricsReportingEnabled();
-#endif
-#else
-  return false;
-#endif
-}
+}  // namespace metrics