This reverts the following commits (but keeps the other recent changes
to gmain.c):
 • e4ee3079 Do not wake up main loop if change is from same thread
 • 20870240 main: Create a helper function for "owner wakeup" optimization
 • 0c0469b5 gmain: Signal wakeups if context has never been acquired as well
 • 9ba95e25 gmain: only signal GWakeup right before or during a blocking poll

Some combination of them is causing problems with LibreOffice and/or
WebKit, and the safest thing to do at the moment is revert them all
until we work out what’s going on. The previous revert (4976e810

) was
not sufficient (it fixed WebKit, but re-broken LibreOffice).

By reverting, we gain some spurious wakeups, but avoid dropping
necessary wakeups, which is presumably what’s causing problems in the
other modules.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

https://bugzilla.gnome.org/show_bug.cgi?id=761102