Firing Timer should use foreground broadcast

Bug: 17695520

We did a similar fix in the past for b/11122055.

Change-Id: If3c561cad240a156c94410826223664e24f007c7
diff --git a/src/com/android/deskclock/timer/TimerReceiver.java b/src/com/android/deskclock/timer/TimerReceiver.java
index 5bf2bbb..049a114 100644
--- a/src/com/android/deskclock/timer/TimerReceiver.java
+++ b/src/com/android/deskclock/timer/TimerReceiver.java
@@ -217,6 +217,8 @@
         Intent intent = new Intent();
         intent.setAction(Timers.TIMES_UP);
         intent.setClass(context, TimerReceiver.class);
+        // Time-critical, should be foreground
+        intent.addFlags(Intent.FLAG_RECEIVER_FOREGROUND);
         if (!mTimers.isEmpty()) {
             intent.putExtra(Timers.TIMER_INTENT_EXTRA, timerId);
         }