Interpret the size in the configure event as window geometry

The size of the configure event has always been specified as in window
geometry coordinates, but it was never implemented this way.
shell: Replace set_margin with set_window_geometry

Currently, there is a fun flicker when toggling maximization or
fullscreen on a window in mutter or more sophisicated compositors
and WMs.

What happens is that the client want so go maximized, so we
calculate the size that we want the window to resize to (640x480),
and then add on its margins to find the buffer size (+10 = 660x500),
and then send out a configure event for that size. The client
renders to that size, realizes that it's maximized, and then
says "oh hey, my margins are actually 0 now!", and so the compositor
has to send out another configure event.

In order to fix this, make the the configure request correspond to
the window geometry we'd like the window to be at. At the same time,
replace set_margin with set_window_geometry, where we specify a rect
rather than a border around the window.
xdg-shell: Fix documentation

request_change_state has been folded into the configure event.
tests: add expect_protocol_error function

This function checks if a particular protocol error came in wire.
It's usefull in the cases where we hitherto used FAIL_TEST.
The problem with FAIL_TEST is that *any* assert will pass the test,
but we want only some asserts to pass the test (i. e. we don't
want the test to pass when it, for example, can't connect to display).
FAIL_TESTs are good only for sanity testing.

The expect_protocol_error allows us to turn all FAIL_TESTs to TESTs
as will be introduced in following patches.

v2: fixed white-space error and a mistake in comment

Reviewed-by: Bryce Harrington <b.harrington@samsung.com>
Reviewed-by: Pekka Paalanen <ppaalanen@gmail.com>
tests: add frame_callback_wait_nofail

With expect_protocol_error, we need a possibility to wait for a frame
without aborting the test when wl_display_dispatch returns -1;
This patch adds function frame_callback_wait_nofail that only
returns 1 or 0 (instead of aborting on error).

Reviewed-by: Pekka Paalanen <ppaalanen@gmail.com>
tests: use expect_protocol_error in tests

Turn FAIL_TESTs to TESTs. FAIL_TESTs are bad...

Reviewed-by: Pekka Paalanen <ppaalanen@gmail.com>
compositor: keep track of the weston_layer a weston_view is in

This introduces a new struct, weston_layer_entry, which is now used
in place of wl_list to keep the link for the layer list in weston_view
and the head of the list in weston_layer.
weston_layer_entry also has a weston_layer*, which points to the layer
the view is in or, in the case the entry it's the head of the list, to
the layer itself.
compositor: add a masking mechanism to weston_layer

this adds a mechanism to mask the views belonging to a layer
to an arbitrary rect, in the global space. The parts that don't fit
in that rect will be clipped away.
Supported by the gl and pixman renderer only for now.
xwayland: set surface_id to 0 when client resource is found

When Xwayland requests that a wl_surface be created and the X event is
handled before the wayland requests, a surface ID is stored to
window->surface_id and the window is added to the unpaired window list. When
weston_wm_create_surface is called, the window is removed from the list and
window->surface_id is set to zero. If window->surface_id is not zero when
weston_wm_window_destroy is called, the window is assumed to be in the
unpaired window list and wl_list_remove is called. If
weston_wm_window_handle_surface_id is called and the surface has already
been created, the window is not added to the unpaired window list, but
window->surface_id isn't set to zero. When the window is destroyed, removing
the window from the list is attempted anyway and a crash occurs.

This patch stores the surface ID in a temporary variable and only assigns it
to window->surface_id when the window is added to the unpaired window list.
Otherwise window->surface_id is set to zero to maintain its use as a flag
variable.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=80273
Signed-off-by: Tyler Veness <calcmogul@gmail.com>
xwayland/window-manager: Rename a variable for clerity
xwayland: Better handle a race with X

If X windows are created and destroyed very fast sometimes the WM window
object gets created and destroyed before we get around to handling client
messages.  Failing to check that the window is still valid can result in a
segfault.
compositor: quick fix for sub-surface mapping

If a client does this:
1. create a main window and map it
2. create a wl_surface, and make it a sub-surface of the main window
3. set the sub-surface to desync
4. commit content to the sub-surface to map it

Then step 4 should cause the sub-surface to become mapped. However,
Weston fails to schedule a repaint in that case, so the sub-surface will
not appear until something else causes a repaint on that output, e.g.
the main window.

A quick and dirty fix is to set the output mask for the surface in
Weston, which allows the repaint to be scheduled. This patch implements
that, and might only work right on single-output systems.

A proper fix would involve rewriting the whole "is surface mapped"
mechanism in Weston, to not rely on output assignments but to have a
separate flag for "mapped", and figuring out how to schedule repaints
for the right outputs.

Following is the actual protocol sequence used to trigger the problem:

[3224648.125]  -> wl_compositor@4.create_surface(new id wl_surface@3)
[3224648.206]  -> xdg_shell@7.get_xdg_surface(new id xdg_surface@8, wl_surface@3)
[3224648.311]  -> xdg_surface@8.set_title("simple-shm")
[3224648.378]  -> wl_surface@3.damage(0, 0, 250, 250)
[3224649.888]  -> wl_shm@6.create_pool(new id wl_shm_pool@9, fd 6, 250000)
[3224650.031]  -> wl_shm_pool@9.create_buffer(new id wl_buffer@10, 0, 250, 250, 1000, 1)
[3224650.244]  -> wl_shm_pool@9.destroy()
[3224651.975]  -> wl_surface@3.attach(wl_buffer@10, 0, 0)
[3224652.100]  -> wl_surface@3.damage(20, 20, 210, 210)
[3224652.243]  -> wl_surface@3.frame(new id wl_callback@11)
[3224652.317]  -> wl_surface@3.commit()
[3228652.535]  -> wl_compositor@4.create_surface(new id wl_surface@12)
[3228652.610]  -> wl_subcompositor@5.get_subsurface(new id wl_subsurface@13, wl_surface@12, wl_surface@3)
[3228652.644]  -> wl_subsurface@13.set_desync()
[3228652.659]  -> wl_subsurface@13.set_position(100, 100)
[3228654.090]  -> wl_shm@6.create_pool(new id wl_shm_pool@14, fd 6, 250000)
[3228654.140]  -> wl_shm_pool@14.create_buffer(new id wl_buffer@15, 0, 250, 250, 1000, 1)
[3228654.180]  -> wl_shm_pool@14.destroy()
[3228654.408]  -> wl_surface@12.attach(wl_buffer@15, 0, 0)
[3228654.436]  -> wl_surface@12.damage(0, 0, 250, 250)
[3228654.462]  -> wl_surface@12.commit()

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Cc: George Kiagiadakis <george.kiagiadakis@collabora.com>
Cc: Jason Ekstrand <jason.ekstrand@intel.com>