[Libreoffice] [PATCH] GTK: remove menu when we press the alt key

[xapantu]

Hi,

Here is a patch to remove the menu when the alt key is pressed, it is
not the case with GTK apps, and is disturbing. And the code to show the
menu wasn't at the right place, so, even if we should have this menu, it
is dirty IMO.

See this Launchpad bug:
https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/123500

And this OOo bug:
http://qa.openoffice.org/issues/show_bug.cgi?id=80604


Lucas

PS: this time, I used git format-patch, tell me if there is any problem.