Clear emergency dialer task on launch

Bug: 20344056
Change-Id: Ic26f003acad3f9f91d772e5b4be8bd4b8aff5ec8
diff --git a/src/com/android/phone/EmergencyDialer.java b/src/com/android/phone/EmergencyDialer.java
index b9597c1..c7dd1e9 100644
--- a/src/com/android/phone/EmergencyDialer.java
+++ b/src/com/android/phone/EmergencyDialer.java
@@ -123,7 +123,7 @@
         @Override
         public void onReceive(Context context, Intent intent) {
             if (Intent.ACTION_SCREEN_OFF.equals(intent.getAction())) {
-                finish();
+                finishAndRemoveTask();
             }
         }
     };