Added UMA metrics for screen capture UI in the status area.

ash/common/system/chromeos/screen_security/screen_share_tray_item.cc

Index: ash/common/system/chromeos/screen_security/screen_share_tray_item.cc
diff --git a/ash/common/system/chromeos/screen_security/screen_share_tray_item.cc b/ash/common/system/chromeos/screen_security/screen_share_tray_item.cc
index ccd2364297dd87bd45ed0bd3858677c9dd37a99e..a868f239e3eae7dcd2c3f70c96511684d0466a74 100644
--- a/ash/common/system/chromeos/screen_security/screen_share_tray_item.cc
+++ b/ash/common/system/chromeos/screen_security/screen_share_tray_item.cc
@@ -77,6 +77,14 @@ std::string ScreenShareTrayItem::GetNotificationId() {
   return kScreenShareNotificationId;
 }
 
+void ScreenShareTrayItem::RecordStoppedFromDefaultViewMetric() {
+  // Intentionally not recording a metric.
+}
+
+void ScreenShareTrayItem::RecordStoppedFromNotificationViewMetric() {
+  // Intentionally not recording a metric.
+}
+
 void ScreenShareTrayItem::OnScreenShareStart(
     const base::Closure& stop_callback,
     const base::string16& helper_name) {