Since we're now connecting to one more signal of MetaWaylandOutput, keep
signal connections in one place and move connecting the
"output-destroyed" signal to surface_entered_output() and disconnecting
it to surface_left_output().
This also allows us to use the "outputs_to_destroy_notify_id" as a
simple set and rename it to "outputs".
While at it, also use g_hash_table_destroy() instead of
g_hash_table_unref() since destroy is more clear than unref and does the
same thing in this case.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1230
When hotplugging a new monitor, we recreate all the MetaWaylandOutputs
and need to emit leave events to the surfaces for the old wl_outputs and
enter events for the newly created ones.
There's a race condition though: We might update the monitors a surface
is on (and thus emit enter/leave events for the wl_outputs) before the
Wayland client is registered with the new wl_output (ie. the
bind_output() callback of MetaWaylandOutput was called), which means we
don't send an enter event to the client in surface_entered_output().
Since MetaWaylandSurface now has the MetaWaylandOutput in its outputs
hashtable, it thinks the client has been notified and won't send any
more enter events.
To fix that, make MetaWaylandOutput emit a new signal "output-bound"
when a client bound to the output and make all surfaces which are on
that output listen to the signal. In the signal handler compare the
newly added client to the client the surface belongs to, and if it's the
same one, send an enter event to that client.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1230
This will check whether the current backing buffer is compatible with
the primary plane of the passed CoglOnscreen. Since this will extend the
time before a buffer is released, the MetaWaylandBufferRef is swapped
and orphaned if a new buffer is committed before the previous one was
released. It'll eventually be released, usually by the next page flip
callback.
Currently implemented for EGLImage and DMA-BUF buffer types.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/798
Currently a buffer use count always reaches zero before it is replaced.
This is due to the fact that at the point a new buffer is attached, the
last potential user releases it (the stage) since the currently
displayed frame has a composited copy of the buffer.
This may however change, if a buffer is scanned out directly, meaning it
should not be released until the page flip callback is invoked.
Prepare for this by making the buffer reference a heap allocated struct,
enabling us to keep a pointer to it longer than the buffer is attached.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/798
This is so that cogl-trace.h can start using things from cogl-macros.h,
and so that it doesn't leak cogl-config.h into the world, while exposing
it to e.g. gnome-shell so that it can make use of it as well. There is
no practical reason why we shouldn't just include cogl-trace.h via
cogl.h as we do with everything else.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1059
There are two surface roles owning a MetaWindow: MetaWaylandShellSurface
(basis of MetaWaylandXdgToplevel, MetaWaylandXdgPopup,
MetaWaylandWlShellSurface, etc), and MetaXwaylandSurface.
With these two role types, the MetaWindow has two different types of
life times. With MetaWaylandShellSurface, the window is owned and
managed by the role itself, while with MetaXwaylandSurface, the
MetaWindow is tied to the X11 window, while the Wayland surface and its
role plays more the role of the backing rendering surface.
Before, for historical reasons, MetaWindow was part of
MetaWaylandSurface, even though just some roles used it, and before
'wayland: Untie MetaWindowXwayland lifetime from the wl_surface' had
equivalent life times as well. But since that commit, the management
changed. To not have the same fied in MetaWaylandSurface being managed
in such drastically different ways, rearrange it so that the roles that
has a MetaWindow themself manages it in the way it is meant to; meaning
MetaWaylandShellSurface practically owns it, while with Xwayland, the
existance of a MetaWindow is tracked via X11.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/835
The role determines how a relative coordinate is calculated. More
specifically, using clutters API to transform coordinates is only
accurate right after a clutter layout pass but this function is used
e.g. to deliver pointer motion events which can happen at any time. This
isn't a problem for Wayland clients since they don't control their
position, but X clients do and we'd be sending outdated coordinates if a
client is moving a window in response to motion events.
This was already done already, but now move the Xwayland specific logic
to the Xwayland surface role, keeping the generic transformation logic
in the generic actor surface role.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/835
The shell surface role is the one where subsurfaces may exist, and it
has direct relation to the MetaWindowActorWayland which currently has
the subsurface stacking logic.
Instead of directly finding the window actor when dealing with
subsurfaces, notify the parent surface that the subsurface state
changed, so that it can outsource the application of this information to
the role. For subsurface roles, this simply means forward upward to the
parent; for shell surface roles, this means regenerate the surface actor
layering.
This allows us to move away from accessing the window directly from the
surface, which in turn allows us to change the ownership structure of
windows.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/835
When mapping/unmapping windows, an animation may be played which can
change the actual actor size and location, hence defeating picking if
done too early.
Make sure we repick when the affects are completed, once the actor is
sized and placed.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1026
As with most other state that ends up being pushed to the actor and the
associated shaped texture, also push the texture and the corresponding
metadata from the actor surface. This fixes an issue when a toplevel
surface was reset, where before the subsurface content was not properly
re-initialized, as content state synchronization only happened on
commit, not when asked to synchronize.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
Similar to wl_list_foreach(), add
META_WAYLAND_SURFACE_FOREACH_SUBSURFACE() that iterates over all the
subsurfaces of a surface, without the caller needing to care about
implementation details, such as leaf nodes vs non-leaf nodes.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
The vfunc is not called when a surface commits its state, but when the
state is applied. Make this clearer by changing the name to
"apply_state" (and "pre_apply_state").
https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
This changes how asynchronous window configuration works. Prior to this
commit, it worked by MetaWindowWayland remembering the last
configuration it sent, then when the Wayland client got back to it, it
tried to figure out whether it was a acknowledgment of the configuration
or not, and finish the move. This failed if the client had acknowledged
a configuration older than the last one sent, and it had hacks to
somewhat deal with wl_shell's lack of configuration serial numbers.
This commits scraps that and makes the MetaWindowWayland take ownership
of sent configurations, including generating serial numbers. The
wl_shell implementation is changed to emulate serial numbers (assuming
each commit acknowledges the last sent configure event). Each
configuration sent to the client is kept around until the client one. At
this point, the position used for that particular configuration is used
when applying the acknowledged state, meaning cases where we have
already sent a new configuration when the client acknowledges a previous
one, we'll still use the correct position for the window.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
This moves the cached subsurface surface state into the generic
MetaWaylandSurface namespace. Eventually it'll be used by other surface
roles which as well aim to implement synhcronization.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
The name didn't communicate it was about surface state, and it somewhat
confusingly had the name "pending" in it, which could be confused with
the fact that while it's used to collect pending state, it's also used
to cache previously committed pending state.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
With the eventual aim of exposing the internals of MetaWaylandSurface
outside of meta-wayland-surface.c, make users of the pending state use a
helper to fetch it. While at it, rename the struct field to something
more descriptive.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
This is inspired by 98892391d7 where the usage of
`g_signal_handler_disconnect()` without resetting the corresponding
handler id later resulted in a bug. Using `g_clear_signal_handler()`
makes sure we avoid similar bugs and is almost always the better
alternative. We use it for new code, let's clean up the old code to
also use it.
A further benefit is that it can get called even if the passed id is
0, allowing us to remove a lot of now unnessecary checks, and the fact
that `g_clear_signal_handler()` checks for the right type size, forcing us
to clean up all places where we used `guint` instead of `gulong`.
No functional changes intended here and all changes should be trivial,
thus bundled in one big commit.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/940
The actor is already in surface coordinate space, so we should not scale
with the buffer scale to transform surface coordinates to stage
coordinates.
This bug causes input method using wayland text-input protocol to
receive wrong cursor location. Reproduced in ibus (when candidate
window is open) with scaling factor other than 1.
This commit also fixes pointer confinement.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/915
Syncronized subsurfaces that call into `merge_pending_state` might
otherwise not create new destroy handlers, ending up with a invalid
handler ids, throwing errors and leaking.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/868
For the most part, a MetaWindow is expected to live roughly as long as
the associated wl_surface, give or take asynchronous API discrepancies.
The exception to this rule is handling of reparenting when decorating or
undecorating a window, when a MetaWindow on X11 is made to survive the
unmap/map cycle. The fact that this didn't hold on Wayland caused
various issues, such as a feedback loop where the X11 window kept being
remapped. By making the MetaWindow lifetime for Xwayland windows being
the same as they are on plain X11, we remove the different semantics
here, which seem to lower the risk of hitting the race condition causing
the feedback loop mentioned above.
What this commit do is separate MetaWindow lifetime handling between
native Wayland windows and Xwayland windows. Wayland windows are handled
just as they were, i.e. unmanaged together as part of the wl_surface
destruction; while during the Xwayland wl_surface destruction, the
MetaWindow <-> MetaWaylandSurface association is simply broken.
Related: https://gitlab.freedesktop.org/xorg/xserver/issues/740
Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/762https://gitlab.gnome.org/GNOME/mutter/merge_requests/774
Make it possible to listen for damage on a window actor. For X11, the
signal is emitted when damage is reported; for Wayland, it is emitted
when any of the surfaces associated with the window is damaged.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/752
Flatten the subsurface actor tree, making all surface actors children
of the window actor.
Save the subsurface state in a GNode tree in MetaWaylandSurface, where
each surface holds two nodes, one branch, which can be the tree root
or be attached to a parent surfaces branch, and a leaf, which is
used to save the position relative to child branch nodes.
Each time a surface is added or reordered in the tree, unparent all
surface actors from the window actor, traverse all leaves of the
tree and readd the corresponding surface actors back to the window
actor.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/664
Now that MetaShapedTexture is a ClutterContent implemetation that
is aware of its own buffer scale, it is possible to simplify the
event translation routines.
Set the geometry scale in MetaSurfaceActor, and stop adjusting the
surface scale when translating points. Also remove the now obsoleted
meta_wayland_actor_surface_calculate_scale() function.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
MetaWindowActor is the compositor-side representative of a
MetaWindow. Specifically it represents the geometry of the
window under Clutter scene graph. MetaWindowActors are backed
by MetaSurfaceActors, that represent the windowing system's
surfaces themselves. Naturally, these surfaces have textures
with the pixel content of the clients associated with them.
These textures are represented by MetaShapedTexture.
MetaShapedTextures are currently implemented as ClutterActor
subclasses that override the paint function to paint the
textures it holds.
Conceptually, however, Clutter has an abstraction layer for
contents of actors: ClutterContent. Which MetaShapedTexture
fits nicely, in fact.
Make MetaShapedTexture a ClutterContent implementation. This
forces a few changes in the stack:
* MetaShapedTexture now handles buffer scale.
* We now paint into ClutterPaintNode instead of the direct
framebuffer.
* Various pieces of Wayland code now use MetaSurfaceActor
instead of MetaShapedTexture.
* MetaSurfaceActorWayland doesn't override size negotiation
vfuncs anymore
https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
When 252e64a0ea moved the texture
ownership to MetaWaylandSurface, it failed to handle the case when a
NULL-buffer is attached, leaving the texture reference in place. This
caused issues when the surface should have been hidden (e.g. attaching a
NULL buffer to a cursor surface for hiding the cursor sprite).
Related: https://gitlab.gnome.org/GNOME/mutter/issues/630
Prior to this commit, MetaWaylandSurface held a reference to
MetaWaylandBuffer, who owned the texture drawn by the surface. When
switching buffer, the texture change with it.
This is problematic when dealing with SHM buffer damage management, as
when having one texture per buffer, damaged regions uploaded to one,
will not follow along to the next one attached. It also wasted GPU
memory as there would be one texture per buffer, instead of one one
texture per surface.
Instead, move the texture ownership to MetaWaylandSurface, and have the
SHM buffer damage management update the surface texture. This ensures
damage is processed properly, and that we won't end up with stale
texture content when doing partial texture uploads. If the same SHM
buffer is attached to multiple surfaces, each surface will get their own
copy, and damage is tracked and uploaded separately.
Non-SHM types of buffers still has their own texture reference, as the
texture is just a representation of the GPU memory associated with the
buffer. When such a buffer is attached to a surface, instead the surface
just gets a reference to that texture, instead of a separately allocated
one.
Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/199
This adds the required bits to wayland surfaces and ties them up
to the compositor parts.
It is based on and very similar in nature to buffer transforms.
From the specification:
> The global interface exposing surface cropping and scaling
> capabilities is used to instantiate an interface extension for a
> wl_surface object. This extended interface will then allow cropping
> and scaling the surface contents, effectively disconnecting the
> direct relationship between the buffer and the surface size.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/323
When destructing a xdg_toplevel, we'll disassociate the actor from the
MetaWaylandSurface, to allow it to animate out. After having done this,
avoid trying to set it as unreactive when unsetting the window.
This fixes the runtime warning:
clutter_actor_set_reactive: assertion 'CLUTTER_IS_ACTOR (actor)' failed
Before processing the buffer damage region, intersect it with the buffer
rectangle to avoid trying to damage content outside the surface.
This fixes the runtime warning "GL error (1281): Invalid value"
happening when a client posts too large buffer damage larger.
This adds the required bits to wayland surfaces and ties them up
to the compositor parts.
The central part here is to recalculate the surface size accordingly
and to translate surface damage into buffer damage.
The choosen approach additionally lays groundwork for wp_viewporter
support, which is closely related in its nature.
A further explanation of buffer transforms from the specification:
> The purpose of this request is to allow clients to render content
> according to the output transform, thus permitting the compositor
> to use certain optimizations even if the display is rotated.
> Using hardware overlays and scanning out a client buffer for
> fullscreen surfaces are examples of such optimizations.
It is meant to hold surfaces that require a ClutterActor, just like wl/xdg
shell surfaces and subsurfaces. Make it inherit from MetaWaylandActorSurface
so it gets that for free.
The type declaration is also made completely private, in order to avoid
cyclic dependency between meta-wayland-surface.h and
meta-wayland-actor-surface.h. We just require the GType fro assign_role()
anyway.
The order and way include macros were structured was chaotic, with no
real common thread between files. Try to tidy up the mess with some
common scheme, to make things look less messy.
Sometimes it may be useful for roles to put callbacks in the generic
surface frame callback queue. The surface frame callback queue will
either eventually be processed on the next surface role assignment that
places the frame callbacks in a role specific queue, processed at some
other point in time by a role, or cleaned up on surface destruction.
https://gitlab.gnome.org/GNOME/mutter/issues/240
Clients using EGLStream-backed buffers will expect the stream to be
functional after wl_surface::attach(). That means the compositor-side
stream must be created and a consumer attached to it.
To resolve the above, this change realizes buffers even when the attach
operation is deferred (e.g. synchronized subsurfaces).
https://bugzilla.gnome.org/show_bug.cgi?id=782575
To check if a subsurface is effectively synchronized, we walk the
subsurface hierarchy to look for a non-subsurface parent or a subsurface
being synchronized.
However, when client is closing, the parent surface might already be
gone, in which case we end up with a surface being NULL which causes a
NULL pointer dereference and a crash.
Check if the parent surface is NULL to avoid the crash, and consider
it's already synchronized if it is NULL to avoid further updates.
Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/124
We used to maintain an actor for cursors, even though we would possibly
use hw overlays or even some other overlay actor for those. This happens
no more, so check whether we are dealing with an actor-backed surface role
before fiddling with it.
All surface roles that do need a backing actor inherit from this
class, it makes sense to move actor management there. This also
means the MetaWaylandActorSurface is in charge of emitting
::geometry-changed on the MetaWaylandSurface.
Instead of scheduling a meta_later, keep track of the unassociated
windows, and look for matches as soon as the MetaWaylandSurface is
created on our side.
This will ensure the surface is given the Xwayland role before receiving
the first wl_surface.commit.
In the synchronized subsurface case, the destination list may
contain other elements from previous wl_surface.commit calls.
Resetting the list will leave those dangling frame callbacks
that will lead to invalid writes when those get to be destroyed
(eg. on client shutdown).
When moving the pending state of an effectively synchronized subsurface
so it is applied together with the parent, perform a merge of the source
MetaWaylandPendingState into the destination one, instead of simply
overwriting the struct.
The other approach had 2 kind of leaks, one that would happen everytime
a wl_surface.commit happens on a sync subsurface (both surface/buffer
damage regions are leaked). The other more unlikely one would apply on
the rest of pending state data, happening whenever the compositor gets
>1 wl_surface.commit calls on the subsurface before the parent surface
gets its own.
The function has also been renamed to use the more descriptive "merge"
term.
Related: gnome-shell#64
Compositor effects change the actor size and position, which can lead to
inconsistent output enter/leave notifications, leaving clients' surfaces
without any output set.
Update output enter/leave notifications after all compositor effects are
completed so that we give clients accurate output location.
Closes: https://gitlab.gnome.org/GNOME/mutter/issues/104
Make the Wayland objects push the state relevant to their role to the
MetaSurfaceActor instead of MetaSurfaceActorWayland pulling the state
from the associated surface.
This makes the relationship between the actor and the objects that
constructs it more clear; the actor is a drawable that the protocol
objects control, not the other way around.
This will make it easier to "detach" a surface actor from a surface,
which is necessary when unmapping a window while the underlying surface
is yet to be destroyed and potentially reused.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/5https://bugzilla.gnome.org/show_bug.cgi?id=791938
This commit moves out non-core wl_surface related code into separate
code units, while renaming types to fit a common scheme. The changes
done are:
* ClutterActor based surface roles built upon
MetaWalyandSurfaceRoleActorSurface. This object has been renamed to
MetaWaylandActorSurface and related functionality has moved into
meta-wayland-actor-surface.c.
* The code related to roles backed by a MetaWindow (i.e. built upon
MetaWaylandShellSurface) was moved into meta-wayland-shell-surface.c
* The majority of subsurface related code was moved into into
meta-wayland-subsurface.c and the object was renamed
MetaWaylandSubsurface.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/5https://bugzilla.gnome.org/show_bug.cgi?id=791938
The handlers depend on a role being assigned. Destroying the window
causes it to become unmapped, which would sometimes trigger one of the
handlers, resulting in an is-assigned assert hitting in one of the
handlers. Avoid this by disconnecting the handlers earlier, so that
there is no risk that any them being triggered before the role is
assigned.
https://bugzilla.gnome.org/show_bug.cgi?id=789552
Both notify::position on the surface actor and position-changed on
MetaWindow are listened to, in order to trigger wl_output updates for
wl_surfaces whenever the surfaces move across them.
Both signals are necessary in order to cater for toplevel and subsurface
relocations (Because it's the parent window actor what changes position
in this last case).
Also, shuffle signal disconnection, so each signal goes away with
the object reference held by MetaWaylandSurface.
https://bugzilla.gnome.org/show_bug.cgi?id=782344
Add a mechanism to MetaWaylandSurface that inhibits compositor's own
shortcuts when the surface has input focus, so that clients can receive
all key events regardless of the compositor own shortcuts.
This will help with implementing "fake" active grabs in Wayland and
XWayland clients.
https://bugzilla.gnome.org/show_bug.cgi?id=783342
A client can still commit state to a destroyed subsurface. It wont
update anything on the screen, since the subsurface will not be
visible, but mutter should still handle it and not crash.
https://bugzilla.gnome.org/show_bug.cgi?id=781391
It checks whether a surface is on a given "logical monitor", not
output. Output here is the Wayland name for the same thing, but should
not be confused with MetaOutput.
https://bugzilla.gnome.org/show_bug.cgi?id=777732
In preparation for further refactorizations, rename the MetaMonitorInfo
struct to MetaLogicalMonitor. Eventually, part of MetaLogicalMonitor
will be split into a MetaMonitor type.
https://bugzilla.gnome.org/show_bug.cgi?id=777732
Commit 5eb5f72 - wayland: Check surface outputs after mapped state
changes connected the ::mapped signal handler, we need to disconnect it
on destroy to avoid a possible assertion failure in
update_surface_output_state()
https://bugzilla.gnome.org/show_bug.cgi?id=776036
This commit adds for a new type of buffer being attached to a Wayland
surface: buffers from an EGLStream. These buffers behave very
differently from regular Wayland buffers; instead of each buffer
reperesenting an actual frame, the same buffer is attached over and
over again, and EGL API is used to switch the content of the OpenGL
texture associated with the buffer attached. It more or less
side-tracks the Wayland buffer handling.
It is implemented by creating a MetaWaylandEglStream object, dealing
with the EGLStream state. The lifetime of the MetaWaylandEglStream is
tied to the texture object (CoglTexture), which is referenced-counted
and owned by both the actors and the MetaWaylandBuffer.
When the buffer is reattached and committed, the EGLStream is triggered
to switch the content of the associated texture to the new content.
This means that one cannot keep old texture content around without
copying, so any feature relying on that will effectively be broken.
https://bugzilla.gnome.org/show_bug.cgi?id=773629
Add support for inverted Y Wayland buffers. OpenGL textures are by
default inverted, so adding support for EGL_WAYLAND_Y_INVERTED_WL
effectively means adding support for non-inverted, which makes the
MetaShapedTexture apply a transformation when drawing only when querying
EGL_WAYLAND_Y_INVERTED_WL resulted in the response "EGL_FALSE".
https://bugzilla.gnome.org/show_bug.cgi?id=773629
Don't rely on the Cogl layer having Wayland specific paths by
determining the buffer type and creating the EGLImage ourself, while
using the newly exposed CoglTexture from EGLImage API. This changes the
API used by MetaWaylandSurface to make the MetaWaylandBuffer API be
aware when the buffer is being attached. For SHM and EGL buffers, only
the first time it is attached will result in a new texture being
allocated, but later for EGLStream's, more logic on every attach is
needed.
https://bugzilla.gnome.org/show_bug.cgi?id=773629
Move the MetaWaylandSurface::destroy signal before starting the actual
destruction, in wl_surface_destructor, so that all fields (e.g. surface
role) are intact when the listeners are invoked.
https://bugzilla.gnome.org/show_bug.cgi?id=771050
Implement min/max size request from xdg-shell-v6 and plug it into the
existing code so that windows with fixed size cannot be tiled/maximized
in Wayland just like in X11.
Bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=770226
If cogl fails to create a texture from the client's given buffer,
mutter would raise a fatal error and terminate.
As a result, a broken client might kill gnome-shell/mutter and take the
entire Wayland session with it.
Instead of raising a fatal error in this case, log the cogl error
message and send the client an OOM error, so mutter/gnome-shell can
survive an unsupported buffer size.
https://bugzilla.gnome.org/show_bug.cgi?id=770387
Rely on the actor surface role's commit function for queuing frame
callbacks. This also makes the surface actor state synchronization work
again, which was broken by 'wayland: Sync surface actor state in actor
role commit handler'.
https://bugzilla.gnome.org/show_bug.cgi?id=770131
Don't check whether the surface of the role has a window, but whether
the corresponding toplevel surface has a window. This is necessary to
make subsurfaces not always early out.
https://bugzilla.gnome.org/show_bug.cgi?id=770131
There is nothing stopping a subsurface from commiting its state before
its parents role has been assigned. Thus, we need to handle
meta_wayland_surface_get_toplevel() returning NULL for subsurfaces even
on commit.
Make sure to always call the parent role commit vfunc, so that they can
handle updating their state properly.
This means other places need to handle the situation where
surface->window is NULL on commit. This may for example happen when the
parent of a modal dialog is unmapped or NULL is attached to a
wl_shell_surface.
https://bugzilla.gnome.org/show_bug.cgi?id=769936
Emit a 'configure' signal before configuring the role. This will enable
extensions to send its own configure events before the role is
configured.
https://bugzilla.gnome.org/show_bug.cgi?id=769936