Revert "Remove empty collab_test.js"

This reverts commit 4f364c5f20.

package.json

@@ -60,7 +60,7 @@
         "c9.ide.language.javascript.tern": "#a65ad88dd9",
         "c9.ide.language.javascript.infer": "#30801a51a2",
         "c9.ide.language.jsonalyzer": "#722983bf96",
-        "c9.ide.collab": "#05a15421a7",
+        "c9.ide.collab": "#5450834758",
         "c9.ide.local": "#2bfd7ff051",
         "c9.ide.find": "#989c06e6a7",
         "c9.ide.find.infiles": "#28b3cfcb47",