RevisionParserTest: Uncomment test that now works

Change-Id: Icbae14e44a477cc521082f53e9cefbc7e44a9a2a
diff --git a/javatests/com/google/gitiles/RevisionParserTest.java b/javatests/com/google/gitiles/RevisionParserTest.java
index f287685..26dccc5 100644
--- a/javatests/com/google/gitiles/RevisionParserTest.java
+++ b/javatests/com/google/gitiles/RevisionParserTest.java
@@ -173,9 +173,7 @@
     assertThat(parser.parse("master~1..master"))
         .isEqualTo(
             new Result(Revision.peeled("master", commit), Revision.peeled("master~1", parent), ""));
-    // TODO(dborowitz): 2a2362fbb in JGit causes master~2 to resolve to master
-    // rather than null. Uncomment when upstream regression is fixed.
-    //assertThat(parser.parse("master~2..master")).isNull();
+    assertThat(parser.parse("master~2..master")).isNull();
     assertThat(parser.parse("other..master"))
         .isEqualTo(
             new Result(Revision.peeled("master", commit), Revision.peeled("other", other), ""));