Update base/timer.h code to pass through Location from call sites.

chrome/browser/sync/engine/sync_scheduler.cc

Index: chrome/browser/sync/engine/sync_scheduler.cc
diff --git a/chrome/browser/sync/engine/sync_scheduler.cc b/chrome/browser/sync/engine/sync_scheduler.cc
index 993b72755abcd019a89a4ff8380c7a91d5c9dbac..73c4f1517f87cf1c770b879d75cc26ef9cea31da 100644
--- a/chrome/browser/sync/engine/sync_scheduler.cc
+++ b/chrome/browser/sync/engine/sync_scheduler.cc
@@ -875,14 +875,14 @@ void SyncScheduler::AdjustPolling(const SyncSessionJob* old_job) {
 
   // Adjust poll rate.
   poll_timer_.Stop();
-  poll_timer_.Start(poll, this, &SyncScheduler::PollTimerCallback);
+  poll_timer_.Start(poll, this, &SyncScheduler::PollTimerCallback, FROM_HERE);
 }
 
 void SyncScheduler::RestartWaiting() {
   CHECK(wait_interval_.get());
   wait_interval_->timer.Stop();
   wait_interval_->timer.Start(wait_interval_->length,
-                              this, &SyncScheduler::DoCanaryJob);
+                              this, &SyncScheduler::DoCanaryJob, FROM_HERE);
 }
 
 void SyncScheduler::HandleConsecutiveContinuationError(
@@ -1050,7 +1050,7 @@ void SyncScheduler::OnSilencedUntil(const base::TimeTicks& silenced_until) {
   wait_interval_.reset(new WaitInterval(WaitInterval::THROTTLED,
                                         silenced_until - TimeTicks::Now()));
   wait_interval_->timer.Start(wait_interval_->length, this,
-      &SyncScheduler::Unthrottle);
+      &SyncScheduler::Unthrottle, FROM_HERE);
 }
 
 bool SyncScheduler::IsSyncingCurrentlySilenced() {