Bug 1208373 - Fix test_peerConnection_capturedVideo.html to wait for close() promise. r=jib

MozReview-Commit-ID: AOrm5JkfxAG

--HG--
extra : rebase_source : 3ff50ff74c3acf33feeb8dfe6539d080df6f3aa9
extra : intermediate-source : 7f2842b199f5f377de64b130e0e8f8f0867abd3b
extra : source : b9c629250c90c42950b2b91ccf248dd1da6cdbf5

dom/media/tests/mochitest/test_peerConnection_capturedVideo.html

@@ -73,8 +73,8 @@ function startTest(media, token) {
                         (e.code ? " (code=" + e.code + ")" : "") +
                         " in test for " + media.name +
                         (e.stack ? ":\n" + e.stack : "")))
+  .then(() => test && test.close())
   .then(() => {
-    if (test) { test.close(); }
     removeNodeAndSource(video);
     manager.finished(token);
   })