Work around Tizen DRM test failure

Instead of hanging while we wait for key status events that will never
come, move on after 5 seconds.

Issue #891

Change-Id: Ia338401097fb29039fa203729d0efaa4cca5623b

test/media/drm_engine_integration.js

@@ -215,7 +215,11 @@ describe('DrmEngine', function() {
               // This was probably a PlayReady persistent license.
             }
           }).then(function() {
-            return keyStatusEventSeen;
+            // Some platforms (notably 2017 Tizen TVs) do not fire key status
+            // events.  This is a temporary workaround for the test failure
+            // in https://github.com/google/shaka-player/issues/891
+            var keyStatusTimeout = shaka.test.Util.delay(5);
+            return Promise.race([keyStatusTimeout, keyStatusEventSeen]);
           }).then(function() {
             var call = onKeyStatusSpy.calls.mostRecent();
             if (call) {