RFR: JDK-8191204 Post-consolidation cleaning up of the build system
I think this is the last round of the post-consolidation cleaning up of
the build system. I'm removing some now-redundant checks, aligning to
more common calling practice, and speeding up the hg status check (which
was becoming more urgent as the repo grow in size).
Erik reminded me off-list that the check for gtest source code could not
be removed, due to the fact that Oracle, for historical reasons,
generates "source bundles" with incomplete source trees, which e.g. are
missing gtest. (And since gtest is built as part of the hotspot product,
and not as a separate build step, it cannot be not built by just
omitting a make target, so we must have this test.)
I reverted this part before checking in the patch, judging that no
re-review was needed.