Launch overlay emergency app by feature flag

Add feature flag to launch overlay emergency app instead of Emergency Info
app for teamfood in the future.

Test: Manually
Bug: 118809382
Change-Id: I618f7aafe0c3896adcd072f5b254d03936e83c16
diff --git a/src/com/android/phone/EmergencyInfoGroup.java b/src/com/android/phone/EmergencyInfoGroup.java
index 5c01834..6ce10aa 100644
--- a/src/com/android/phone/EmergencyInfoGroup.java
+++ b/src/com/android/phone/EmergencyInfoGroup.java
@@ -126,7 +126,8 @@
 
         if (infos != null && infos.size() > 0) {
             final String packageName = infos.get(0).activityInfo.packageName;
-            final Intent intent = new Intent(TelephonyManager.ACTION_EMERGENCY_ASSISTANCE)
+            final Intent intent = new Intent(
+                    EmergencyAssistanceHelper.getIntentAction(getContext()))
                     .setPackage(packageName);
             setTag(R.id.tag_intent, intent);
             setUserIcon();