Record the number of tabs in a session restore in SampledProfile

chrome/browser/metrics/perf_provider_chromeos.cc

Index: chrome/browser/metrics/perf_provider_chromeos.cc
diff --git a/chrome/browser/metrics/perf_provider_chromeos.cc b/chrome/browser/metrics/perf_provider_chromeos.cc
index 1873e2e3fc208726334917114446aa9bc2e1d3e5..6bb48a3bef87c1f86d7d55ec51eae18ae9894c05 100644
--- a/chrome/browser/metrics/perf_provider_chromeos.cc
+++ b/chrome/browser/metrics/perf_provider_chromeos.cc
@@ -210,7 +210,7 @@ void PerfProvider::SuspendDone(const base::TimeDelta& sleep_duration) {
                           collection_delay));
 }
 
-void PerfProvider::OnSessionRestoreDone() {
+void PerfProvider::OnSessionRestoreDone(int num_tabs_restored) {
   // Do not collect a profile unless logged in as a normal user.
   if (!IsNormalUserLoggedIn())
     return;
@@ -245,7 +245,8 @@ void PerfProvider::OnSessionRestoreDone() {
       collection_delay,
       base::Bind(&PerfProvider::CollectPerfDataAfterSessionRestore,
                  weak_factory_.GetWeakPtr(),
-                 collection_delay));
+                 collection_delay,
+                 num_tabs_restored));
 }
 
 void PerfProvider::OnUserLoggedIn() {
@@ -347,11 +348,13 @@ void PerfProvider::CollectPerfDataAfterResume(
 }
 
 void PerfProvider::CollectPerfDataAfterSessionRestore(
-    const base::TimeDelta& time_after_restore) {
+    const base::TimeDelta& time_after_restore,
+    int num_tabs_restored) {
   // Fill out a SampledProfile protobuf that will contain the collected data.
   scoped_ptr<SampledProfile> sampled_profile(new SampledProfile);
   sampled_profile->set_trigger_event(SampledProfile::RESTORE_SESSION);
   sampled_profile->set_ms_after_restore(time_after_restore.InMilliseconds());
+  sampled_profile->set_num_tabs_restored(num_tabs_restored);
 
   CollectIfNecessary(sampled_profile.Pass());
   last_session_restore_collection_time_ = base::TimeTicks::Now();