Fix crash of update-over-cellular icon

chrome/browser/chromeos/upgrade_detector_chromeos.cc

Index: chrome/browser/chromeos/upgrade_detector_chromeos.cc
diff --git a/chrome/browser/chromeos/upgrade_detector_chromeos.cc b/chrome/browser/chromeos/upgrade_detector_chromeos.cc
index 4178576bc484b20ffaa56b5c6b6771f0a9ff992d..c84d67a8d0ecb07f36d9c0718eb8df358d540c0a 100644
--- a/chrome/browser/chromeos/upgrade_detector_chromeos.cc
+++ b/chrome/browser/chromeos/upgrade_detector_chromeos.cc
@@ -102,7 +102,7 @@ void UpgradeDetectorChromeos::UpdateStatusChanged(
   } else if (status.status ==
              UpdateEngineClient::UPDATE_STATUS_NEED_PERMISSION_TO_UPDATE) {
     // Update engine broadcasts this state only when update is available but
-    // downloading over cellular connection requires user's agreement
+    // downloading over cellular connection requires user's agreement.
     NotifyUpdateOverCellularAvailable();
   }
 }