Conflicts exist if move to jdk14

[Man Cao]

I just fast forwarded the "default" branch to JDK14-GA.
$ hg up default
$ hg pull -r jdk-14-ga http://hg.openjdk.java.net/jdk/jdk
$ hg push -b default
We are also discussing the proper way to do a rebase/merge.
I also prefer rebase to merge, but it seems OpenJDK projects are mainly
using merge (e.g. loom).

I suppose it is challenging to ask Jie to do the rebase/merge work, unless
Jie becomes a Committer to tsan project first.
I don't know how to make a webrev for the conflict-resolving changes during
the rebase/merge process.

-Man