Maximizing window after fullscreening it in weston desktop shell

[Boyan Ding]

  The handling about window states has been improved recently but there
still seems some problem with that.

  When I was running weston-stacking with yesterday's snapshot of weston
(weston-stacking in 1.5.0 is much more troublesome), I found if I press
m (maximize) multiple times after fullscreening it, the fullscreened
window will become brighter and brighter because the window is opaque
and is drawn again and again instead of drawing on the black view.

  After analysing the code, I found when a window is requesting to
maximize when it's fullscreen, we now will configure it for
fullscreening again. And the black view somehow doesn't come to the
front and we directly draw the new surface on the original one.

  I want to ask several question about it:
1. Is the behavior I talked about a desired behavior?
2. If not. How should we deal with that?

  For 1, I think that's undesired. And for 2, I came up with two ideas.
One way is to ignore the maximizing request when it is (or will be)
fullscreen. The other is to handle that in later stages of
configuration. I don't know which is more appropriate.

  I'm still studying wayland and weston code, so feel free to point out
my misunderstandings.

Thanks,
Boyan Ding