Add telecom log to report when call changes external state.

Bug: 29906222
Change-Id: Id3c6e70d7922d83b84c533e60cd665c0f6d3d1d3
diff --git a/src/com/android/server/telecom/Call.java b/src/com/android/server/telecom/Call.java
index b3e36f9..c9dc852 100644
--- a/src/com/android/server/telecom/Call.java
+++ b/src/com/android/server/telecom/Call.java
@@ -1037,7 +1037,7 @@
             if (wasExternal != isExternal) {
                 Log.v(this, "setConnectionProperties: external call changed isExternal = %b",
                         isExternal);
-
+                Log.event(this, Log.Events.IS_EXTERNAL, isExternal);
                 for (Listener l : mListeners) {
                     l.onExternalCallChanged(this, isExternal);
                 }
diff --git a/src/com/android/server/telecom/Log.java b/src/com/android/server/telecom/Log.java
index 7f12404..5a397fd 100644
--- a/src/com/android/server/telecom/Log.java
+++ b/src/com/android/server/telecom/Log.java
@@ -167,6 +167,7 @@
         public static final String RECEIVE_VIDEO_RESPONSE = "RECEIVE_VIDEO_RESPONSE";
         public static final String SEND_VIDEO_REQUEST = "SEND_VIDEO_REQUEST";
         public static final String SEND_VIDEO_RESPONSE = "SEND_VIDEO_RESPONSE";
+        public static final String IS_EXTERNAL = "IS_EXTERNAL";
 
         public static class Timings {
             public static final String ACCEPT_TIMING = "accept";