This is required for proper integration with any other library/application that
may perform wayland API calls and poll() the wayland fd from multiple threads.
Using wl_display_dispatch{_queue}() is thread-safe if not mixed with custom
poll() usage, which GSource/GMainContext does.
Essentially, the problem is that multiple threads polling and reading
the same fd is extremely racy. Use the wayland provided API for allowing
concurrent access to the wayland display fd.
See the wayland man pages for wl_display_prepare_read(),
wl_display_cancel_read() and wl_display_read_events() for more details.
https://bugzilla.gnome.org/show_bug.cgi?id=763852
WINBOOL is MinGW-specific, so change it to BOOL, which is universally
available.
Also, Visua Studio is more picky on where __stdcall (WINAPI) is placed, so
fix that to be in-sync with what is done in the other sources.
Use of g_signal_handlers_disconnect_by_func() needs to do more work than
necessary to find all the matching handlers. Instead, just hold on to the
signal identifier and remove it directly so we hit the fast path.
Not terribly ground breaking in terms of performance gains, but its done
enough to be worthwhile.
https://bugzilla.gnome.org/show_bug.cgi?id=766049
The active keyboard grab can be spared then. This way the passive
key grabs allow other key combinations (eg. alt-tab) that are not
mandatory to grab here.
The wayland specification for discrete step information for scroll and
other axes reads:
| The discrete value carries the directional information. e.g. a
| value of -2 is two steps towards the negative direction of this axis.
mutter sets a value of 1 for SCROLL_DOWN events and -1 for SCROLL_UP
events.
gdkdevice Wayland backend does the opposite, it translates a positive
discrete value as SCROLL_UP and a negative value as SCROLL_DOWN, which
ends up inverting the scrolling direction.
Fix the logic in gdkdevice Wayland to use a positive value as
SCROLL_DOWN and a negative value as SCROLL_UP so that it matches mutter
and weston logic.
https://bugzilla.gnome.org/show_bug.cgi?id=765907
If the monitor vfuncs are not implemented in a display class,
fall back to providing a single monitor object representing
the entire screen. This is not meant to be 'good enough', it
is just to provide some implementation until all backends
implement the monitor vfuncs. When that is the case, the
fallback should be removed.
NoSymbol is not a valid GDK symbol (it only has the concept of
VoidSymbol, for some reason, which is neither the same thing nor
produced by any sane keymap). Passing NoSymbol events through to GTK+
apps is unlikely to produce anything useful.
In particular, this meant VTE would scroll to the end of the buffer when
pressing Fn (required for Page Up/Down on Macs), as it was receiving a
keypress that wasn't a modifeir. This does not happen on X11, as the
KEY_FN keycode is above 255, so does not get sent to clients.
https://bugzilla.gnome.org/show_bug.cgi?id=764825
We don't care about the specific (possibly client-side) window that
requested the focus here, only the toplevel. Fixes mistakenly sent
focus events when the grab happens inside the current focus window.
https://bugzilla.gnome.org/show_bug.cgi?id=762756
Always associate a drag context with a GdkDisplay and use that when
getting a cursor for a given action.
If we don't do this, dragging on a window that doesn't use the default
display will make us use cursors from the wrong display.
https://bugzilla.gnome.org/show_bug.cgi?id=765565
Typically, there won't be any references on old frame timings except for
the most recent timing. So instead of discarding these and re-entering
gslice twice, just steal the old frame timing and reuse it.
https://bugzilla.gnome.org/show_bug.cgi?id=765592
Don't track all orphaned dialogs globally, as mixing them up with each
other would in most cases trigger errors when we try to pass bogus
values to Wayland requests.
https://bugzilla.gnome.org/show_bug.cgi?id=765474
The naming of pointers to GdkWaylandDisplay's were inconsistent.
Running the following commands in gtk+/gdk/wayland illustrate the
inconsistency:
$ grep -r '\<display_wayland\>' *.[ch] | wc -l
195
$ grep -r '\<wayland_display\>' *.[ch] | wc -l
81
This patch renames all occurrences of "wayland_display" to
"display_wayland". This is also consistent with naming in the X11
backend. A couple of whitespace changes were done as well in places
where the rename was already done, that added line breaks to long lines
that stood out.
https://bugzilla.gnome.org/show_bug.cgi?id=765474
When synthesizing keyboard repeat, we can potentially drift further from
the mark depending on the timing of the frame callback and how long it
took to deliver the event.
This patch attempts to reduce this by tracking from a stable epoch the
time of our next keyboard repeat.
https://bugzilla.gnome.org/show_bug.cgi?id=765567
This allows us to decide when the R and B color channels should be
flipped with a much better granularity.
For instance, when using GLX_EXT_texture_from_pixmap to create a GL
texture from a surface we don't need to swap the R and B channels, as
the internal representation of the texture data will already have the
appropriate colors.
We also don't need to flip color channels when blitting from a texture.
Cairo surfaces are in BGRA format, but we upload them as RGBA buffers on
GLES; this means that the R and B channels are flipped in the texture
data.
Instead of doing a costly channel flip before putting them on the GPU,
we can flip the values inside the GLSL shader we use specifically for
GLES.
We cannot use GL_BGRA and GL_UNSIGNED_INT_8_8_8_8_REV when reading back
from the frame buffer in the software fallback path, as they do not
exist on OpenGL ES.
This will make the slow path a bit slower, because of the implicit
format conversion.
When uploading a Cairo image surface to a GL texture we cannot use
GL_BGRA and GL_UNSIGNED_INT_8_8_8_8_REV on OpenGL ES, as they do not
exist in the core spec.
On some platforms we can ask the GL context machinery to create a GLES
context, instead of a GL one.
In order to ask for a GLES context at GdkGLContext realization time, we
use a bit field like we do for forward compatible, or debug contexts.
The 'use-es' bit also changes the way we select a default version,
because OpenGL and OpenGLES versions differ.
https://bugzilla.gnome.org/show_bug.cgi?id=743746
Windows save in hardware_keycode an information which is not so low
level and some application require the hardware scancode.
As Windows provides this information save it in GdkEventPrivate
and provide a function to get this information.
For no Windows system the function return the hardware_keycode instead.
Signed-off-by: Frediano Ziglio <fziglio@redhat.com>
https://bugzilla.gnome.org/show_bug.cgi?id=765259
This first adds a common autotools module that can be included by
the Makefile.am's to generate the file lists and the g-ir-scanner/
g-ir-compiler command lines to build the introspection files.
The autotools files for gdk/ and gtk/ are then updated to generate
the full file lists needed to build the introspection files, with
the full command lines for g-ir-scanner and g-ir-compiler as NMake
Makefile modules that can be used to build the introspection files
for Visual Studio builds.
https://bugzilla.gnome.org/show_bug.cgi?id=765195
These were showing up higher in Sysprof profiles.
The simple fix is to avoid the emit_by_name() and let the interface emit
the signals directly. No function preconditions are provided since these
are internal API.
If we get gdk_wayland_seat_flush_frame_event() with no previous event to be
flushed, we fallback into the scroll event checks. However, there's no check
performed there as to whether it really scrolled, so it'd always send a smooth
scroll event with 0/0 deltas in this case.
This should be mostly harmless, but still, we should only end up emitting scroll
events if those really happened.
The frame event is also meant to compress wl_pointer.leave events, at this
point the focus surface will be definitely NULL. In the end, wl_pointer.frame
should flush the last composed event despite the pointer focus.
https://bugzilla.gnome.org/show_bug.cgi?id=765065
We must emit the cancel event with the same semantics, and towards the GdkWindow
that is currently under the touchpoint, so make proxy_button_event() deal with
GDK_TOUCH_CANCEL.
Fixes the GDK_TOUCH_CANCEL event being emitted only on the toplevel, which is
usually non-sufficient.
Since Wayland is using libxkbcommon, it inherits X unfortunate
real/virtual modifier distinction, so we have to do the same
gymnastics we do for X to map between the two.
This should fix matching of accelerators using virtual modifiers
(modulo gnome-shell bugs regarding the handling of Super).
https://bugzilla.gnome.org/show_bug.cgi?id=764424
MoveWindow should not be used over the pre-existing move/resize
functions, which already correctly position a window with respect
to its parent, while also taking into account the size of window
decorations.
https://bugzilla.gnome.org/show_bug.cgi?id=765100
gdk_window_reparent() already changes children list for old and new parent.
Doing so twice results in a circular reference in the list, which can hang
the application later, for example in gtk_window_show().
https://bugzilla.gnome.org/show_bug.cgi?id=764845
This makes usage of _gdk_display again when creating a window.
This is needed because there is a window created when the display
is being initialized, so it becomes a chicken and egg problem.
For now we roll back this to fix the wintab crash but we might
want to fix this again in the future by improving the wintab
initialization.
https://bugzilla.gnome.org/show_bug.cgi?id=764664
The zoom/rotate change for quartz does not build on 10.7. This change
adds zoom/rotate support in quartz only for 10.8 and following. The
problems is described here:
https://bugzilla.gnome.org/show_bug.cgi?id=760276 and here
https://trac.macports.org/ticket/51052
NSEventPhaseMayBegin was only introduced in 10.8 although documentation
says it is introduced in 10.7. Tests on 10.7 indicate that the phase
property for the Magnify event is not supported at all on 10.7
On wayland, such axes are per-tool, we must update device capabilities
on the fly as new tools enter proximity, first the slave device so
it matches the current tool, and then the master device so it looks
the same than the current slave device.
Only the management of tablets and tools is added so far. No tablet events
are yet interpreted.
As it's been the tradition in GTK+, erasers are split into their own device,
whereas the rest of the tools are meant to be routed through the
GDK_SOURCE_PEN device. Both pen/eraser devices are slaves to a master
pointer device, separate to wl_pointer's. This is so each tablet can
maintain its own cursor/positioning accounting.
Signed-off-by: Stephen Chandler Paul <thatslyude@gmail.com>
This will enable multiple "pointers" to have separate data here.
Will come out useful when adding support for tablets, as they
will have a separate cursor for all purposes.
Because there are multiple different types of styluses that can be used with
tablets, we have to have some sort of identifier for them attached to the
GdkDeviceTool, especially since knowing the actual tool type for a GdkDeviceTool
is necessary for matching up a GdkDeviceTool with it's appropriate
GdkInputSource in Wayland (eg. matching up a GdkDeviceTool eraser with the
GDK_SOURCE_ERASER GdkInputSource of a wayland tablet).
Signed-off-by: Stephen Chandler Paul <thatslyude@gmail.com>
On the devices and backends that support it, this signal will be emitted
on slave/floating devices whenever the tool they are interacting with
changes. These notifications may also work as a sort of proximity events,
as the tool will be unset when the pen moves too far.
For backends, gdk_device_update_tool() has been included, all that should
be done on their side is just calling this whenever any tool might have
changed.
GdkDeviceTool is an opaque object that can be used to identify a given
tool (eg. pens on tablets) during the app/device lifetime. Tools are only
set on non-master devices, and are owned by these.
The accounting functions are made private, the only public call on
GdkDeviceTool so far is gdk_device_tool_get_serial(), useful to identify
the tool across runs.
This fixes a bug that was introduced by db1b24233e.
The reason why 0:0 coordinates were passed was that SWP_NOREPOSITION was
misinterpreted as SWP_NOMOVE. That is not the case - SWP_NOREPOSITION
prevents owner Z-order change, not the window position change.
gnome-control-center is calling gtk_window_resize() on configure-event
signals which leads to a busy loop.
Avoids such a busy loop by not re-configuring a window with the same
size, unless this is coming from and xdg-shell configure.
bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=764374
When we invalidate a window we need to also invalidate all child windows
that are native (non-native are automatically invalidated as we track
invalidation once per native window only). This was done in a pretty
inefficient way, recursing over the entire tree.
This makes the invalidation much faster by only looking at the native
children of the native window we're in, filtering out those that
are not a descendant of the client side window we're interested in.
Given that there are very few native subwindows this is much faster.
Currently only one kind of decorative window is in use - the shape
indicator that is shown when snapping windows to the edge of the screen.
When normal toplevel class is used, its window procedure expects certain
motions from GDK (passing user data to CreateWindowEx(), registering
handle in a hash map etc), and might crash if that is not done.
Dumb window doesn't require anything, it can just be.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
Now halfleft/halfright/fullup snaps do hug screen edges as intended.
Documents AeroSnap behaviour when snapped windows are drag-resized
(currently this implementation handles this in a very simplistic way).
Don't believe GTK when it tells us that window shadow is 0, preserve
previous values (but do remember that GTK wants no shadow, in case
we need that).
Fixes a couple of bugs in unsnapping (check offset against the half
of the window; don't put pointer in the middle of the window vertically
if it still fits in the top half).
https://bugzilla.gnome.org/show_bug.cgi?id=763013
Implements gdk_win32_window_set_shadow_width().
Uses shadow width/height to adjust max tracking size, allowing
windows to be drag-resized to cover the whole desktop.
Also uses SM_C*VIRTUALSCREEN instead of SM_C*MAXTRACK.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
Indicator is a bare layered click-through native window,
painted completely by GDK, including animation.
This commit also isolates some of the more spam-ish debug logging
under ifdef.
This commit also changes the system metric used for maximal window
height for the snapping purposes. Turns out, SM_CYMAXTRACK is way
too large, use SM_CYVIRTUALSCREEN instead.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
This implements the part of AeroSnap that snaps windows when you
drag them (while moving or resizing) to the edge of the screen.
It also fixes drag behaviour for snapped and maximized windows
(if such windows are dragged, first they must be unmaximized/unsnapped).
Note that this code does not take into account the shadow width, and
because of that the under-pointer-position-preserving window moves
might not look as such for maximized windows, which lack the shadow
when maximized, but do have the shadow when unmaximized.
This commit also doesn't cover some corner-cases the same way AeroSnap does.
Also, the snapping indicator (which is supposed to be a window shape that
shows where the window will be if the drag op is stopped at its current
point) is not being drawn, all routines responsible for its creation,
moving and drawing are stubs.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
This is what AeroSnap does. If a window is being unsnapped on
a new monitor, check if the work area is large enough for the
window to fit in its normal size. If the window fits, just
reposition it so that the ratio of
left-window-edge-to-screen-edge / right-window-edge-to-screen-edge
remains the same, without scaling the window.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
It works exactly like AeroSnap.
Except for shift+win+left/right, which is left for AeroSnap
to handle (AeroSnap takes action before we get the message,
so there's no way for us to override it).
The only thing that doesn't work is shift+win+left/right on
a maximized window, for reasons unknown at the moment.
This only implements winkey+stuff behaviour of AeroSnap,
not the drag-to-the-edge-and-something-funny-happens one.
https://bugzilla.gnome.org/show_bug.cgi?id=763013
If a layered window was hidden and is made visible, erase its
contents before showing it. GDK will schedule a redraw, but until
then we generally don't want to show old contents.
https://bugzilla.gnome.org/show_bug.cgi?id=763783
This is achieved by sending undocumented message WM_SYSMENU
to the window.
Before doing that, the window is given WS_SYSMENU style
(to enable window menu) and some combination of
WS_MAXIMIZEBOX (for "Mazimize" item)
WS_MINIMIZEBOX (for "Minimize" item)
WS_SIZEBOX (for "Size" item)
depending on which operations are currently permissible.
WM_SYSMENU is processed by DefWindowProc(), which results
in showing the window menu. We remove extra styles
at the first opportunity (WM_INITMENU message), as they
alter the way our window is rendered.
https://bugzilla.gnome.org/show_bug.cgi?id=763851
These functions are supposed to return the numbers of consecutive
1 bits in each components mask as precision. However, due to a
copy-paste mistake when this code was moved around in
commit 70d689cddd, the precision
was always reported as zero. This affects only a few applications
that directly set window background on X11 windows, such as emacs.
https://bugzilla.gnome.org/show_bug.cgi?id=764210
Delay as long as possible before calling OpenClipboard(),
call CloseClipboard() as quickly as possible after that.
Don't call OpenClipboard() when we don't need to (for example,
we don't need to open clipboard to call GetClipboardOwner()).
Also, print out actual W32 error code in some cases where it
was not printed before.
https://bugzilla.gnome.org/show_bug.cgi?id=763907
Error codes can be easily looked up in an error code list
and/or googled up. Error messages, while descriptive, often
describe the wrong thing, and the messages themselves are not
part of the documentation of a function, unlike error codes.
It would be preferable to have the code, or both.
https://bugzilla.gnome.org/show_bug.cgi?id=763913
gtk+ currently depends on the scaling factor and the cairo device scale
of both the backend surfaces and image surfaces to be equal.
Until now we didn't apply a cairo device scale at all and depended on the
automatic scaling of CGContexts. This works when drawing with cairo but
fails in case of image surfaces, which get requested at a too small size.
To make the quartz backend behave more like the X11 one, set the cairo device
scale on the surface in gdk_quartz_ref_cairo_surface(). As this conflicts
with the default scaling done by CGContext (we would get double scaling)
undo the CGContext scaling using CGContextScaleCTM().
This patch is based on the following patches by Brion Vibber:
https://bugzilla.gnome.org/show_bug.cgi?id=740199#c4https://bugs.freedesktop.org/show_bug.cgi?id=69796#c4https://bugzilla.gnome.org/show_bug.cgi?id=763779
If the configure-event gives us the same size as we had before,
which is common for animation resizes, then try to keep the
existing buffer around. This saves us a memfd_create() syscall
on every frame.
https://bugzilla.gnome.org/show_bug.cgi?id=763350
Now that GdkWaylandDeviceData is gone, the functions prefixed
"gdk_wayland_device_" and taking a GdkWaylandSeat as first
parameter feel out of place. Renaming those makes it more obvious
that it's seat functions.
https://bugzilla.gnome.org/show_bug.cgi?id=763859
It's the same than gdk_device_get_seat() nowadays. Also, rename the
usages of GdkWaylandDeviceData to GdkWaylandSeat in the functions
affected by the removal.
https://bugzilla.gnome.org/show_bug.cgi?id=763859
We were just relying on the drag context finalize() to destroy
the window. But with garbage-collected bindings, that might
not happen as soon as we like, so explicitly hide the window
when the drag ends successfully.
https://bugzilla.gnome.org/show_bug.cgi?id=763659
Using UpdateLayeredWindow() on iconic windows brings them *back* from
their iconic (minimized) state. That is bad.
As a precaution, also don't use SetWindowPos() on iconic windows.
This means that iconic windows can't be moved. That is fixable
by using SetWindowPlacement(), but there is no pressing need to do so,
as there are very few cases when windows need to be moved while minimized.
https://bugzilla.gnome.org/show_bug.cgi?id=763835
Two errors here:
1) A typo in splashscreen rectangle calculation - sets right twice
instead of setting top
2) Centering for dialogs is off because it doesn't convert
GDK virtual desktop coordinates to Windows WM virtual desktop
coordinates by adding _gdk_offset_*
https://bugzilla.gnome.org/show_bug.cgi?id=763628
The way gdk_drag_status() may be called multiple times during the
processing of drag and drop events throughout the widget hierarchy
brings some superfluous messaging going in, esp. when it's the last
request the one we want to honor, yet we emit messaging requests on
all.
This is barely appreciable in the X11 backend, but due to the design
of the wayland protocol, quick series of changes like this it have
some self-amplificating consequences which may end up flooding the
connection.
We can delegate this to a late "commit" call, performed within GDK
event management. This way gdk_drag_status() calls may be cached
and only result in windowing messaging once per ::drag-motion or
::drag-data-received event. Emitting the final status will also
avoid spurious action changes on the compositor and the other peer.
https://bugzilla.gnome.org/show_bug.cgi?id=763298
This code:
> gdk_window_get_root_origin (window, &x, &y);
> x -= root_x;
> y -= root_y;
> pointer_window = gdk_device_get_window_at_position (device, &x, &y);
was meant to find the child gdk window at coordinates root_x and root_y.
These 4 lines had 2 bugs:
1) x = x - root_x (same for y) is wrong, it should be x = root_x - x
2) gdk_device_get_window_at_position() does not give you the window
at position x and y. It gives you the window under the device
(mouse pointer) and the returns the device coordinates in x and y.
https://bugzilla.gnome.org/show_bug.cgi?id=763533
MacOS provides the NSEventTypeMagnify which is very similar to the
Gtk ZOOM gesture and NSEventTypeRotate which is very similar to the
Gtk Rotate gesture. Those two event sequences are translated to a
sequence of GDK_TOUCHPAD_PINCH events. This sequence is then detected
in the upper gtk layers as Gtk Zoom/Rotate Gestures.
https://bugzilla.gnome.org/show_bug.cgi?id=760276
When compressing window state events, we didn't free the discarded
event after removing it from the queue, causing us to leak it. This
commit makes sure to free the discarded event after unqueuing it.
https://bugzilla.gnome.org/show_bug.cgi?id=762468
A gtk_surface.present request was added to gtk_surface which takes
timestamp from some input event, and uses that timestamp to figure out
whether the window can be presented or not. If we don't have a
timestamp, we should just give up instead of making up our own,
otherwise we might steal someones focus.
https://bugzilla.gnome.org/show_bug.cgi?id=763037
The gtk_shell protocol used some half baked unstable protocol semantics
that worked by only allowing binding the exact version of the
interface. This hack is a bit too confusing and it makes it impossible
to do any compatible changes without breaking things.
So, instead rename it to include a number in the interface names. This
way we can add requests and events without causing compatibility issues,
and we can later remove requests and events by bumping the number in
the interface names.
https://bugzilla.gnome.org/show_bug.cgi?id=763001
This request actually means nothing to the upper GDK layers,
we used to preempt a GDK_SELECTION_REQUEST event, but this is too
eager, and not like things work in X11.
Originally in wayland, this event may be used for feedback purposes.
We however don't perform any mimetype-based feedback, so we can
safely ignored.
This makes data_source_send() the only place where we actually
trigger GDK_SELECTION_REQUEST, this one is conceptually the same
than the X11 selection request event.
The virtual host assigns the name of the mouse device to
"VirtualBox USB Tablet" in VirtualBox and we'd use that device as mouse.
If not, GtkTooltip is not enabled.
https://bugzilla.gnome.org/show_bug.cgi?id=763017
Other portions of the GDK-Win32 backend make use of this function as
layered windows need to be disabled for GL windows and possibly other
parts, so make this function a private function that is available within
the backend.
https://bugzilla.gnome.org/show_bug.cgi?id=763285
Layered windows and GL do not work well together, so disable layered
windows when initiating a GdkGLContext, so that GtkGLArea programs can run
properly.
Also based on patch by LRN to address the issue.
https://bugzilla.gnome.org/show_bug.cgi?id=763080
The default value for the double-click key in the
org.gnome.settings-daemon.peripherals.mouse schema is 400.
Use the same value as the declared default for the
gtk-double-click-time GTK+ setting, to avoid pointless
differences in corner cases.
https://bugzilla.gnome.org/show_bug.cgi?id=720950
This removes the event_poll_fd global variable and the (ab)use of
get_default_display. It is also more consistent with other backends.
Also store display
Use gdk_window_get_effective_toplevel when looking for
a suitable transient parent, to skip over offscreen windows
that we might encounter in the window tree. This fixes
a crash in glade.
https://bugzilla.gnome.org/show_bug.cgi?id=763110
Fixes bug 763023: in certain circumstances, XRRGetOutputInfo will return
a null pointer. This commit adds a check to detect and handle this
return value.
Otherwise WM-dependent default cursor is used, which does not
match our theme. Worse, later GDK will realize that we have
our own left_ptr cursor and will apply it after all, making
the discrepancy even more noticeable.
https://bugzilla.gnome.org/show_bug.cgi?id=762902
* Explicitly grab the device, setting appropriate cursor on it.
* Fix gdk_device_virtual_set_window_cursor() to just set the
cursor, without trying to check that mouse is over the given
window. Also prevent it from immediately resetting cursor.
* Alse take into account things that happen in other parts of
GDK - don't look for replacement cursor, GDK already did that,
and don't create a default arrow cursor instead of NULL,
GDK-W32 already did that up the stack as well.
Warn about inappropriate cursor == NULL argument instead.
https://bugzilla.gnome.org/show_bug.cgi?id=762711
Toplevels are now true layered windows that are moved,
resized and repainted via UpdateLayeredWindow() API call.
This achieves transparency without any extra effort,
and prevents window size and window contents desychronization
(bug 761629).
This also changes the way CSD windows are detected. We now
use window decorations to detect CSDiness of a window,
and to decide whether a window should be layered (CSD windows should
be) or not.
Decorations are now stored in the window implementation,
not as a quark-based property of the window-as-gobject.
https://bugzilla.gnome.org/show_bug.cgi?id=748872
Normally works only on CSD windows, non-CSD windows continue
to use WM modal loop for drag-resizing and drag-moving. However,
if it is activated on non-CSD windows, it does work.
Has the advantage of being completely immune to AeroSnap.
AeroSnap only worked partially on CSD windows, with the only part
that worked being "don't let users drag window titlebar outside of
the desktop". Now AeroSnap doesn't work on windows moved by
this code at all, which is good, since they currently don't work
well with it due to the way shadows are drawn.
It's possible to also re-implement AeroSnap (or something similar),
but that is a story for another commit.
This code was originally intended to fix the problem of window
size and window contents desynchronization, but failed to achieve
that result in the end. Nevertheless, it serves as a foundation for
other changes to the way window resizing works.
https://bugzilla.gnome.org/show_bug.cgi?id=761629
