Revert IDL compiler build flow to Perl, rename 'deprecated'

To prevent IDL compiler rewrite from slowing down other developers,
we're moving the build flow 100% back to Perl.
We'll then incrementally review and land the Python rewrite, and
when it's 100% done in tree, we'll switch it over in one go.
This way other developers don't need to be concerned with the rewrite.
(I'll handle syncing Perl changes to the Python rewrite.)

This also removes the scary "deprecated" prefix from the Perl, so
people are not discouraged from hacking on it.

Also makes the Python bindings tests optional (not used by default),
so still usable by run-time flag, but not run in presubmit scripts.

BUG=239771

Review URL: https://chromiumcodereview.appspot.com/24156003

git-svn-id: svn://svn.chromium.org/blink/trunk@157996 bbb929c8-8fbe-4397-9dbb-9b2b20218538