Fix disappearing message corner case.

We never properly registered the ExpirationListener, meaning we were
relying on the wait-notify loop of ExpirationManager to delete things.
This normally works, but fails when your phone goes to sleep. So I
properly registered the receiver, and then added a failsafe to re-run
the ExpirationManager if we're about to render an expired message.

Fixes #7906

AndroidManifest.xml

@@ -526,6 +526,8 @@
         </intent-filter>
     </receiver>
 
+    <receiver android:name=".service.ExpirationListener" />
+
 
     <provider android:name=".providers.PartProvider"
               android:grantUriPermissions="true"

src/org/thoughtcrime/securesms/ConversationItem.java

@@ -559,6 +559,10 @@ public class ConversationItem extends LinearLayout
         this.expirationTimer.setExpirationTime(messageRecord.getExpireStarted(),
                                                messageRecord.getExpiresIn());
         this.expirationTimer.startAnimation();
+
+        if (messageRecord.getExpireStarted() + messageRecord.getExpiresIn() <= System.currentTimeMillis()) {
+          ApplicationContext.getInstance(context).getExpiringMessageManager().checkSchedule();
+        }
       } else if (!messageRecord.isOutgoing() && !messageRecord.isMediaPending()) {
         new AsyncTask<Void, Void, Void>() {
           @Override

src/org/thoughtcrime/securesms/service/ExpirationListener.java

@@ -21,6 +21,6 @@ public class ExpirationListener extends BroadcastReceiver {
     AlarmManager  alarmManager  = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
 
     alarmManager.cancel(pendingIntent);
-    alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + waitTimeMillis, pendingIntent);
+    alarmManager.set(AlarmManager.RTC, System.currentTimeMillis() + waitTimeMillis, pendingIntent);
   }
 }

src/org/thoughtcrime/securesms/service/ExpiringMessageManager.java

@@ -46,7 +46,7 @@ public class ExpiringMessageManager {
     }
   }
 
-  void checkSchedule() {
+  public void checkSchedule() {
     synchronized (expiringMessageReferences) {
       expiringMessageReferences.notifyAll();
     }