bug#7013: 23.2; Emacs frame hangs when setting fullscreen parameter to the same current value

["Jan Djärv" <jan.h.d@swipnet.se>]

Dani Moncayo skrev 2010-09-11 18.37:
> Hi there,
>
> My Emacs frame hangs after doing the following:
> 1.- Start emacs with "emacs -Q"
> 2.- Evaluate the Elisp sentence "(set-frame-parameter nil 'fullscreen
> 'maximized)". (this first time the frame gets maximized, OK).
> 3.- Repeat step (2). -->  Now my emacs frame hangs! (C-x C-c still works)
>
> Repeating the maximize sentence didn't have too much sense at that
> point, because the frame was already maximized, but hanging is not
> like the best behaviour anyway.
>
> That same hanging occurs using other values for 'fullscreen (fullboth,
> fullwith, fullheight).
>
> That's all. Thank you.

This is really a bug in Gtk+ and/or your window manager.  Sending many client 
messages to change the state seems to throw them off somehow.  For example, 
the Lucid build has no problems. Sometimes you can make the window responsive 
again by iconifying it an restoring it.  Also, if you have several frames, you 
can switch to another frame and that frame works as normal.  Some events are 
not getting through to the maximized frame, because Gtk+ or the window manager 
is waiting for something.

That said, I made a change so we don't do anything if the requested state is 
the same as the current.  Also, I reduced the number of client messages.

This is in the emacs-23 branch.  It will propagate to the trunk.

	Jan D.