Public EVENT_EMERGENCY_CALLBACK_MODE_ENTER for testing purpose

EVENT_EMERGENCY_CALLBACK_MODE_ENTER needs to be used in a method in PhoneInterfaceManager to trigger emergency callback mode for testing. Therefore, this field needs to be public.

Test: manual
Bug: 178821491
Change-Id: I035e4560d8368e3677f516dce063b90ea2ed1cf4
Merged-In: I035e4560d8368e3677f516dce063b90ea2ed1cf4
diff --git a/src/java/com/android/internal/telephony/Phone.java b/src/java/com/android/internal/telephony/Phone.java
index 8bb388f..9dfbb21 100644
--- a/src/java/com/android/internal/telephony/Phone.java
+++ b/src/java/com/android/internal/telephony/Phone.java
@@ -172,7 +172,8 @@
     protected static final int EVENT_RUIM_RECORDS_LOADED            = 22;
     protected static final int EVENT_NV_READY                       = 23;
     private static final int EVENT_SET_ENHANCED_VP                  = 24;
-    protected static final int EVENT_EMERGENCY_CALLBACK_MODE_ENTER  = 25;
+    @VisibleForTesting
+    public static final int EVENT_EMERGENCY_CALLBACK_MODE_ENTER  = 25;
     protected static final int EVENT_EXIT_EMERGENCY_CALLBACK_RESPONSE = 26;
     protected static final int EVENT_CDMA_SUBSCRIPTION_SOURCE_CHANGED = 27;
     // other