Added asynchronous notification of readiness to the StatisticsProvider, and

chrome/browser/metrics/metrics_service.cc

Index: chrome/browser/metrics/metrics_service.cc
diff --git a/chrome/browser/metrics/metrics_service.cc b/chrome/browser/metrics/metrics_service.cc
index 92ee6021a7e0fea7efb9b6b165200fb54f814285..fa181c316d630462acb5bf3cadbd1fea3f2b1051 100644
--- a/chrome/browser/metrics/metrics_service.cc
+++ b/chrome/browser/metrics/metrics_service.cc
@@ -89,11 +89,10 @@
 // initial log.
 //
 //    INIT_TASK_SCHEDULED,    // Waiting for deferred init tasks to complete.
-// 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.
+// Typically about 30 seconds after startup, a task is posted 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
@@ -247,6 +246,11 @@ const int kSaveStateIntervalMinutes = 5;
 // e.g., the server is down.
 const int kNoResponseCode = content::URLFetcher::RESPONSE_CODE_INVALID - 1;
 
+// Used to indicate that a report was generated before the hardware_class
+// property was available from the StatisticsProvider. This is used to identify
+// faulty reports from Chrome OS clients.
+const char kHardwareClassNotReady[] = "(not ready)";
+
 }
 
 // static
@@ -754,32 +758,22 @@ void MetricsService::InitializeMetricsState() {
   ScheduleNextStateSave();
 }
 
-// static
-void MetricsService::InitTaskGetHardwareClass(
-    base::WeakPtr<MetricsService> self,
-    base::MessageLoopProxy* target_loop) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
-
-  std::string hardware_class;
+void MetricsService::OnStatisticsProviderReady() {
 #if defined(OS_CHROMEOS)
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   chromeos::system::StatisticsProvider::GetInstance()->GetMachineStatistic(
-      "hardware_class", &hardware_class);
-#endif  // OS_CHROMEOS
-
-  target_loop->PostTask(FROM_HERE,
-      base::Bind(&MetricsService::OnInitTaskGotHardwareClass,
-          self, hardware_class));
+      "hardware_class", &hardware_class_);
+#endif
 }
 
-void MetricsService::OnInitTaskGotHardwareClass(
-    const std::string& hardware_class) {
+void MetricsService::InitTaskGetPluginInfo() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK_EQ(state_, INIT_TASK_SCHEDULED);
-  hardware_class_ = hardware_class;
 
   // Start the next part of the init task: loading plugin information.
   PluginService::GetInstance()->GetPlugins(
       base::Bind(&MetricsService::OnInitTaskGotPluginInfo,
-          self_ptr_factory_.GetWeakPtr()));
+                 self_ptr_factory_.GetWeakPtr()));
 }
 
 void MetricsService::OnInitTaskGotPluginInfo(
@@ -834,16 +828,22 @@ void MetricsService::StartRecording() {
     // 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,
+#if defined(OS_CHROMEOS)
+    // The hardware class can only be retrieved once the StatisticsProvider is
+    // ready. This usually happens early enough, but can take longer on some
+    // faulty hardware. Use a temporary special marker to identify those cases.
+    hardware_class_ = kHardwareClassNotReady;

[Ilya Sherman, 2012/04/20 21:18:37]

nit: Any reason not to initialize this in the constructor?

[Joao da Silva, 2012/04/23 09:36:50]

Done.

+    chromeos::system::StatisticsProvider::GetInstance()->WhenReady(
+        base::Bind(&MetricsService::OnStatisticsProviderReady,
+                   self_ptr_factory_.GetWeakPtr()));
+#endif
+
+    // Schedules a delayed task for execution of slower initialization steps
+    // (such as plugin list generation) necessary for sending the initial log.
+    MessageLoop::current()->PostDelayedTask(
         FROM_HERE,
-        base::Bind(&MetricsService::InitTaskGetHardwareClass,
-            self_ptr_factory_.GetWeakPtr(),
-            MessageLoop::current()->message_loop_proxy()),
+        base::Bind(&MetricsService::InitTaskGetPluginInfo,
+                   self_ptr_factory_.GetWeakPtr()),
         base::TimeDelta::FromSeconds(kInitializationDelaySeconds));
   }
 }