Fix issue where expectedListenerUpdate is not stable on test runs.

expectedListenerUpdates is an array of enums, which apparently does not
toString properly.
Changed the toString to generate a comma separated list of the expected
enum values.

Test: Run the BluetoothRouteTransitionTests and verify stable expectedListenerUpdate values.
Fixes: 232553291
Change-Id: I924dba0ba9f02543230e69892e92dc50aa1bcc9e
diff --git a/tests/src/com/android/server/telecom/tests/BluetoothRouteTransitionTests.java b/tests/src/com/android/server/telecom/tests/BluetoothRouteTransitionTests.java
index d923c90..b729f35 100644
--- a/tests/src/com/android/server/telecom/tests/BluetoothRouteTransitionTests.java
+++ b/tests/src/com/android/server/telecom/tests/BluetoothRouteTransitionTests.java
@@ -227,13 +227,16 @@
 
         @Override
         public String toString() {
+            String expectedListenerUpdatesStr = expectedListenerUpdates == null ? ""
+                    : Arrays.stream(expectedListenerUpdates).map(ListenerUpdate::name)
+                            .collect(Collectors.joining(","));
             return "BluetoothRouteTestParameters{" +
                     "name='" + name + '\'' +
                     ", initialBluetoothState='" + initialBluetoothState + '\'' +
                     ", initialDevice=" + initialDevice +
                     ", messageType=" + messageType +
                     ", messageDevice='" + messageDevice + '\'' +
-                    ", expectedListenerUpdate=" + expectedListenerUpdates +
+                    ", expectedListenerUpdate='" + expectedListenerUpdatesStr + '\'' +
                     ", expectedBluetoothInteraction=" + expectedBluetoothInteraction +
                     ", expectedConnectionDevice='" + expectedConnectionDevice + '\'' +
                     ", expectedFinalStateName='" + expectedFinalStateName + '\'' +