Add PROPERTY_DOWNGRADED_CONFERENCE to logging

Bug: 153530054
Test: manual
Change-Id: I37558527ef867b49fc597ae2cdaf1620cfde0ab1
diff --git a/telecomm/java/android/telecom/Connection.java b/telecomm/java/android/telecom/Connection.java
index 9dfa3ac..bb74439 100755
--- a/telecomm/java/android/telecom/Connection.java
+++ b/telecomm/java/android/telecom/Connection.java
@@ -1068,6 +1068,10 @@
             builder.append(isLong ? " PROPERTY_IS_ADHOC_CONFERENCE" : " adhoc_conf");
         }
 
+        if ((properties & PROPERTY_IS_DOWNGRADED_CONFERENCE) == PROPERTY_IS_DOWNGRADED_CONFERENCE) {
+            builder.append(isLong ? " PROPERTY_IS_DOWNGRADED_CONFERENCE" : " dngrd_conf");
+        }
+
         builder.append("]");
         return builder.toString();
     }