JDK 7 M3 status: Open the gates for M4!

[Mark Reinhold]

The test results from b57 are promising, testing of b58 is in progress
with results expected early next week, and there haven't been any new
stabilization requests for a few days.

At this point group integration forests should be considered open for
M4-bound changes, except for any forest that contains pending changes
for M3.  If in doubt, ask your friendly local gatekeeper.

- Mark