RFR Mercurial trees extension: Fixes for hg 4.2-4.5

[Iris Clark]

Hi, Mark.

> http://cr.openjdk.java.net/~mr/rev/trees/

I am not a trees expert, but your changes look fine to me.

> Do we want to use CODETOOLS bug numbers in the trees repo uniformly, going forward?
> What about other hg-tools repos?

I'm for making it easy to maintain these tools.  If a bugid exists, then sure, use it for the commit.  If there is no bugid, I don't think one should be created.  The changeset itself should contain sufficient information to determine why the change was required.

Thanks,
iris