Add a sleep in testSetDismissMessage(), to allow enough time for the dialog to be dismissed.
No failure in 20+ tests.

Bug: 15475633
Change-Id: Ice2a12b09d1e66f35f336a8f3d426cb029e61b6f
diff --git a/tests/tests/app/src/android/app/cts/DialogTest.java b/tests/tests/app/src/android/app/cts/DialogTest.java
index fa90494..4f2e197 100644
--- a/tests/tests/app/src/android/app/cts/DialogTest.java
+++ b/tests/tests/app/src/android/app/cts/DialogTest.java
@@ -812,6 +812,7 @@
         assertTrue(d.isShowing());
         assertFalse(mCalledCallback);
         dialogDismiss(d);
+        Thread.sleep(SLEEP_TIME);
         assertTrue(mCalledCallback);
         assertFalse(d.isShowing());