Back in the day, there was a proposed system of tracking apps in a
specific context.
The inspiration was that you may have used apps in multiple modes:
Firefox may have been used in both "Programmer Reference" and
"Kitten Videos" contexts. Early user response to the feedback wasn't
too positive - context switching is something that humans have trouble
doing implicitly, let alone explicitly. The old codebase still has a
few remnants of this around; let's finally put them to rest.
Note that we still write out a dummy context tag to the XML file - old
versions of the shell will flat out crash if you don't have one of those
in there, so just leave it in for compatibility sake.
https://bugzilla.gnome.org/show_bug.cgi?id=673767
cogl_texture_new() is used in a few places in GNOME Shell, but
it's a deprecated Cogl function. The replacement is the less
verbose cogl_texture_2d_new_with_size(), that is very much a
straightforward replacement.
Remove the few places where this function is used, replacing
it by the CoglTexture2d counterpart.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/287
StTextureCache installs file monitors that invalidate caches when
contents of the underlying file change.
At the moment, the cache uses the Gio.FileMonitorEvent.CHANGED event
type to make that determination.
However, that is suboptimal for at least two reasons:
- while a file is being written to disk, many CHANGED events will be
emitted in sequence. That will cause needless cache invalidations,
and we will risk loading the file before it's fully loaded.
- if an existing file is replaced, e.g. with g_file_replace(), we may
not get a CHANGED event but a CREATED one instead, so the cache ends
up never getting invalidated.
The good news is that in both of those cases GFileMonitor will send a
CHANGES_DONE_HINT event after changes have settled, or after the file
is replaced.
This commit fixes both cases by switching from the CHANGED event to
CHANGES_DONE_HINT to determine that a file has in fact changed.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/286
If the initialization fails for some reason, for example by
running 'gnome-shell --replace', we should not crash because
of an attempt of unregistering an unregistered agent handle.
Fix that by checking if the handle is not NULL before calling
the unregistering routines.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/66
According to Clutter documentation, "[…] actors implementing the
ClutterContainer interface should override the default implementation
of the class handler of this signal and call clutter_actor_destroy()
on their children."
StBin was doing that in GObject:dispose() instead. Move the child
destruction to a new ClutterActor:destroy() vfunc override.
StBoxLayout implements StScrollable, which, semantically, means that
the StBoxLayout size may not match the minimum size reported by the
layout manager. In this specific case, the layout manager by is a
ClutterBoxLayout by default. For example:
+--------------+
| Viewport |
+------+--------------+-----------------+
| | | |
| | | Content |
| | | |
+------+--------------+-----------------+
| |
+--------------+
So, assuming that:
- ContentSize = the minimum size of the content;
- ViewportSize = the allocated size of the viewport;
When allocating StBoxLayout, it must assume ViewportSize, but must
pass ContentSize to the layout manager. That way, the children of
StBoxLayout are correctly placed within it, even if it's bigger than
ViewportSize.
And here's the problem: right now, StBoxLayout assumes ViewportSize
AND also passes it to layout manager. Commit 77c4c6b6d specifically
exposed this bug by relying entirely on StBoxLayout to arrange the
app and window icons.
Fix that by using ViewportSize to allocate StBoxLayout itself, but
passing ContentSize to the layout manager.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/153
gjs now relies entirely on introspection data to determine parent
types and implemented interfaces, so in order to have all methods
and properties resolve correctly, we must include the corresponding
GIRs of all types used.
https://gitlab.gnome.org/GNOME/gnome-shell/issues/574
There's no relation between a window being hidden from overview/taskbars
and a window not being closable - currently we effectively disable the
fallback quit action for any application with open transients, which
simply doesn't make sense.
Instead, only exclude windows for which the close action has been
explicitly disabled.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/217
Using a single resource file for all JS sources saves a couple of
build system instructions, but has some serious downsides:
- bundling the entire shell code with the tools blows
up their size unnecessarily
- the tools are rebuilt unnecessarily for any shell
code change
Autotools was painful enough to let this slip, but with meson we
don't have any excuses - using the actual dependencies speeds up
the build a tiny bit and reduces the tools' sizes from over 2M
to about 50k.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/192
Simply reusing the same dependencies as gnome-shell itself not only
means that we link tons of stuff unnecessarily, but also that we
have to do the whole mutter rpath dance for nothing. Just use the
dependencies those executables actually need for a nice cleanup.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/192
We need this in the main gnome-shell executable in order to locate
the private Shell and St typelibs, but those aren't useful or even
usable in the extension-prefs/portal helper tools.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/192
GSettings now recognizes per-desktop overrides that can be used
to change schemas' default values for a particular desktop. This
is not entirely unlike our existing custom override mechanism in
mutter, except that it is not limited to keys in org.gnome.mutter,
and it doesn't require a separate schema - the latter means that
we (and gnome-teak-tool) no longer have to figure out the correct
schema for the current login session and just use the original one.
https://bugzilla.gnome.org/show_bug.cgi?id=786496
Add a debug command (to be executed manually via Alt+F2) to check
that all of gnome-shell's file descriptors have the CLOEXEC flag set.
This is important so that internal file descriptors do not get passed
to apps when they are launched.
It prints a warning message for every fd that does not have the flag set.
fdwalk() is used from the standard library if available (it is not
available in glibc), otherwise we use the same implementation as glib
has internally.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/132
When the amount of free memory on the system is somewhat low, gnome-shell
will sometimes fail to launch apps, reporting the error:
fork(): Cannot allocate memory
fork() is failing here because while cloning the process virtual address
space, Linux worries that the thread being forked may end up COWing the
entire address space of the parent process (gnome-shell, which is
memory-hungry), and there is not enough free memory to permit that to
happen. This check is somewhat irrelevant because we are only forking
to immediately exec(), which will discard the whole virtual address
space anyway.
This issue can be avoided by using a new optimized gspawn codepath in
the latest glib development version, which uses posix_spawn() internally.
For the optimized codepath to be used, we must not pass a child_setup
function, so the the file descriptor management is reimplemented here
using new glib API to pass fds to the child process. The old API will
continue to be used on older glib versions.
We must also change the spawn flags for this code path to be hit.
I checked that gnome-shell's open file descriptors are all CLOEXEC
so using G_SPAWN_LEAVE_DESCRIPTORS_OPEN should be safe.
This will result in more resilient app launching when memory is low,
since the optimized spawn path avoids cloning the virtual address
space of the parent process (gnome-shell) and avoids the irrelevant
memory overcommit check.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/132
While can_open_new_window() uses some elaborate heuristics to predict
whether an application can open multiple windows, open_new_window()
will always simply relaunch the application. This is often the best
we can do, but when an application provides a "new-window" action in
its .desktop file or on the bus, it is much more likely to work as
expected than blindly activating the app and hoping for a particular
behavior.
https://bugzilla.gnome.org/show_bug.cgi?id=756844
Graphical applications like GIMP or GIMP allow picking colors from
any location on-screen. In order to keep supporting this feature
on wayland and in sandboxed apps, we will expose an appropriate
method in the Screenshot interface, so first add a corresponding
method to ShellScreenshot.
https://gitlab.gnome.org/GNOME/gnome-shell/issues/286
A custom callback type is more convenient, but only as long as no
other callback type is required. We are about to add functionality
that does not return the filename to a screenshot saved on disk, so
prepare for that by moving to GIO's generic async callback pattern.
https://gitlab.gnome.org/GNOME/gnome-shell/issues/286
So that we can be started by systemd --user, instead of gnome-session.
There are three units:
- gnome-shell.service: Start gnome-shell itself.
- gnome-shell-x11.target, gnome-shell-wayland.target: Sync points for
units that need to care if x11 or wayland is in use.
gnome-settings-daemon will use these, for example.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/138
All adjustment setter functions take good care of avoiding emission of
notify:: when it's not needed. The set_property() implementation already
calls into the setter functions, so mark the properties as EXPLICITY_NOTIFY
in order to optimize notify:: emission away through g_object_set (rather
common from JS code).
The actor allocation doesn't change per-se, but apply_transform()
will practically transform it. In order to have the paint volume
update accordingly, queue a relayout.
The default get_paint_volume() implementation will do the union
of children, and the child ClutterText paint volume may expand
beyond StEntry size when text overflows.
We actually want all content to be clipped to the StEntry, so
implement get_paint_volume() and tell it so.
And constrain it in StScrollView instead (instead of falling back to an
infinite paint volume, as the actor as paint/pick impls, but no
corresponding get_paint_volume one).
Fixes artifacts with the AppView (and possibly other places) when paint
volumes are aggressively cached.
Remove any usage of MetaScreen, as it has been removed from libmutter
in the API version 3. The corresponding functionality has been moved
into three different places: MetaDisplay, MetaX11Display (for X11
specific functionality) and MetaWorkspaceManager.
https://bugzilla.gnome.org/show_bug.cgi?id=759538
The default keyed_surface is meant to handle CoglTextures thus we can't
add cairo surfaces to it, as the DestroyNotify function won't handle them.
Then the quicker way is to just add another Hash table for handling
such types of textures, with proper destroy function.
This might cause a crash when cleaning up the cache as the hash table has
cogl_object_unref as DestroyNotify function but that assumes that
the passed object is a valid CoglObject.
Fixes: #210
The instance is owned by the actor (being its child), and thus when the
disposal happens for the parent the text is disposed too, thus it's just
safer to nullify its reference so that we won't try to access to invalid
objects later, and this might be the case since the JS objects could be kept
around until they aren't finalized.
https://bugzilla.gnome.org/show_bug.cgi?id=788931
The gnome-shell-calendar-server calls to refresh queries even when it
has no time range set, which results in:
a) waste of resources (for example after login),
b) many runtime warnings in the journalctl log, related to
incorrect time range being used.
https://gitlab.gnome.org/GNOME/gnome-shell/issues/244
While it is theoretically fine to run --perf=hwtest without passing --hwtest,
the test will hang in this case because it fails to start gedit. Always append
Gedit to the default value for --extra-filter when running the "hwtest" test
to make it work fine without --hwtest.
Call _st_set_text_from_style() when updating the entry's style, so
that CSS style properties such as text-decoration or letter-spacing
are applied over the internal ClutterText instance.
If an actor is pending a relayout when get_allocation_box() is called,
the method forces an allocation update. In case of StWidget, this might
then result in a style update and a consecutive invalidation of the
shadow spec.
A helper method that invalidates one of its parameters as a side effect
(and by extension its return value as well) is most unexpected, so cur-
rently _st_create_shadow_pipeline_from_actor() poses an easy trap to
callers to run into.
Remove that trap by calling get_size()/get_position() instead, which
don't have the unintended side effect - it is still a good idea to fix
callers who were running into this to not waste resources on creating
shadows that are invalidated before the next paint, but throwing un-
defined behavior at them is harsh ...
https://bugzilla.gnome.org/show_bug.cgi?id=788908
The imagedir and userdatadir variables are not fetched from
constants/environment but created with g_strdup*/g_build*. Acknowledge that
and also free the strings in finalize.
Whenever a new cursor image is loaded also save it's hot x/y
coordinates. The drawing code already respects these values, however
they were never set. This change will place the cursor image at the
correct location as seen on screen. shell-screenshot.c served as
reference.
https://bugzilla.gnome.org/show_bug.cgi?id=792860
The st_button_release() call wouldn't happen because StButton does not
set priv->button_mask on touch events. And if we make it called, we can't
try to unset the device grab at the end of the function, as device/sequence
are unset earlier on.
After we receive one of the tracked signals, in case we get stuck inside
the gjs_dumpstack () call, we use an alarm to raise the previously emitted
signal, however without using SA_NODEFER, the raise inside the alarm handler
will be ignored.
To avoid to handle new signals caused by the handler calls, once we get the
first signal, we just ignore them all as they could only lead to dirty traces.
Also, cleaning up a bit the code, and disabling the shell log handler
in dump_gjs_stack_alarm_sigaction since this might lead to a new
gjs_dumpstack () request.
https://bugzilla.gnome.org/show_bug.cgi?id=789237
In order to debug issues triggered by JS code we might need to
see the stack of it, this is not normally visible in static stack traces,
thus we need to call gjs_dumpstack () before dying the process.
Intercepting signals SIGABRT, SIGTRAP (needed for catching fatal glib
errors) SIGFPE and SIGIOT by default, while introducing a new
'backtrace-segfaults' flag for the SHELL_DEBUG environment variable to
do the same on SIGSEGV and SIGBUS (this is a precaution to avoid that we
corrupt the stack for automatic errors trackers).
In any case after dumping the stack we raise the signal again, in order
to make the system aware of it.
https://bugzilla.gnome.org/show_bug.cgi?id=789237
Similar to what it's done in _shell_app_add_window(), rely on calling
shell_app_sync_running_state() when removing windows too, to avoid
transitioning to STOPPED while it's still in the STARTING state.
This makes the logic compliant with the startup notification spec and
prevents stopping an application too early if it has a splash screen
that has been closed before the application's main window is shown.
https://bugzilla.gnome.org/show_bug.cgi?id=787905
Meson now warns when specifying the rpath in linker flags instead
of using the newly added build_rpath option - now that we already
depend on the latest release, there's no reason anyway to not use
the nicer syntax.
https://bugzilla.gnome.org/show_bug.cgi?id=786343
When creating a shadow for a ClutterTexture, we currently use the
underlying CoglTexture directly instead of rendering the actor to
an offscreen buffer. This assumes that the CoglTexture is directly
suitable as shadow source, which isn't necessarily the case - it
may have a very different size than what is shown and scaled up or
down by the hardware. In that case we end up with a scaled shadow
texture as well, which messes up the desired blur effect - the
result will be too light when scaling up, or too sharp when scaling
down. To fix this, only take the shortcut when a ClutterTexture's
underlying texture has the correct size and fall back to offscreen
rendering otherwise.
https://bugzilla.gnome.org/show_bug.cgi?id=788039
If a tray icon gets a mapped and unmapped and the mapped again
in quick succession, we can end up with multiple handlers
listening for window creation events.
This commit tries to guard against that by only listening for
window-created events when we don't know the actor associated
with the icon.
https://bugzilla.gnome.org/show_bug.cgi?id=787361
Unlike pango_font_description_from_string(),
pango_font_description_set_family() requires a already properly
formatted font family string. The proper format is a comma seperated
list of font families, but we generated a "comma space" separated list.
Passing a incorrectly formatted font family string to pango seems to
cause wierd issues, where the wrong font is sometimes selected.
For example, this fixes a font selection issue on zh_TW.UTF-8 locale for
chinese characters, where previously the "Droid Sans" font was selected
instead of "Source Han Sans TW" even though fontconfig had placed
"Source Han Sans TW" before "Droid Sans".
https://bugzilla.gnome.org/show_bug.cgi?id=786868
The theme widget passed to shell_tray_manager_manager_screen() is simply
a means to receive style information. There is nothing which ties the two
object's life cycles together, so it is entirely possible for the tray to
be finalized with the widget still around - we shouldn't try to update the
stale object on widget style changes, so make sure we properly disconnect
the signal handler.
https://bugzilla.gnome.org/show_bug.cgi?id=786526
Compiling the generated source for each consumer of the dependency
means we end up trying to register the enum types multiple times,
resulting in a fatal failure on startup. Luckily code outside libst
itself only depends on the header, which doesn't cause those issues.
st_built_sources contains the source and header generated by mkenums,
not any other generated sources. Clarify that in the name, as we are
about to use source and header separately.
We cannot rely on any build order, except the one we specify ourselves.
St depends on various generated files; other targets depend on those
files existing, so they can be included. There is no direct relationship
between targets and files, unless we declare a dependency, using the
Meson declare_dependency() constructor — which allows us to replace the
various `link_with` directives with the more appropriate `dependencies`
one, and also allows us to specify sources that must exist by the time
we build those targets.
In parallel builds we may end up with st-enum-types.c being built inside
separate targets outside of src/st which may not have the ST_COMPILATION
pre-processor symbol defined. For this reason, we need to define it
ourselves in the source file, before including other headers, to avoid
the single-include guard.
This is not strictly necessary when linking the shell with DT_RPATH as
the runtime paths will be extracted from the introspected libraries and
used from gobject introspection to find them when loading them based on
the typelib files, but when linking with DT_RUNPATH, as it's the case
for some linkers (e.g. ld.gold, or ld.bfd in some distros like Debian).
By explicitly prepending this directory as a library path for GIR, we're
making sure that the wrapped shared objects installed in Mutter's and
GNOME Shell's private directories can be found in all cases.
https://bugzilla.gnome.org/show_bug.cgi?id=777519
Meson is on track to replace autotools as the build system of choice,
so support it in addition to autotools. If all goes well, we'll
eventually be able to drop the latter ...
https://bugzilla.gnome.org/show_bug.cgi?id=783229
When using the meson build system, gvc will be built as a subproject.
As meson restricts submodules to a subprojects/ directory in the
source tree root, move the submodule there.
https://bugzilla.gnome.org/show_bug.cgi?id=783229
libmutter-clutter fixed stage capturing when views are scaled, and for
that to work properly when compositing the screenshot, we need to deal
with the cairo device scale here too.
https://bugzilla.gnome.org/show_bug.cgi?id=765011
Even though the API documentation doesn't say so, the underlying
Cogl texture of a ClutterTexture may be unset, so check for that
case to avoid a runtime warning.
https://bugzilla.gnome.org/show_bug.cgi?id=784353
Otherwise UTC is used which results in a different interpretation of
floating time events. This then could lead to a mismatch with events
generated e_cal_client_generate_instances_sync() which always uses the
default timezone. Such a mismatch would then cause constant invalidation
and reloading.
https://bugzilla.gnome.org/show_bug.cgi?id=781950
This allows a full ClutterActor to be used as hint in the entry, instead
of a simple string.
The string case has been now re-implemented on top of the hint actor.
https://bugzilla.gnome.org/show_bug.cgi?id=783484
This is the same as the previous commit, but for StEntry.
We don't have any need to explicitly destroy this actor in our dispose
implementation, and doing so breaks the assumption that we can access
the clutter_text from within destroy.
https://bugzilla.gnome.org/show_bug.cgi?id=783483
There's no need to explicitly destroy the ClutterText actor inside the
label; doing so is actually harmful, as it will break the normal
reference cycle between container and children.
As StLabel doesn't hold any extra reference to the ClutterText actor and
just uses clutter_actor_add_actor() to add it to itself, let the normal
container dispose cycle run to dispose of the reference.
https://bugzilla.gnome.org/show_bug.cgi?id=783483
The static library was split out to avoid duplicate compilation
of mutter-independent libgnome-shell sources when we had a
wayland/non-wayland split. With the separate libmutter-wayland
library long gone, there's no reason to make the build more
complicated than it needs to be, so fold libgnome-shell-base
back into the regular libgnome-shell.
https://bugzilla.gnome.org/show_bug.cgi?id=783206
Most of the libsecret API was declared stable in 0.18 and the stable API
now provides everything we need, so switch from libsecret-unstable to
libsecret-1.
https://bugzilla.gnome.org/show_bug.cgi?id=782637
Commit ffe4eaf00d broke the handler by fetching the instance private
from the wrong actor - as we don't use the ::primary-icon-clicked signal,
and the ::secondary-icon-clicked signal still works by accident, nobody
noticed until now ...
https://bugzilla.gnome.org/show_bug.cgi?id=782190
When extracting the sliced image, the GTask grants data ownership on
g_task_propagate_*, so the pixbuf list must be properly freed. On async
load, we just left a dangling reference when returning on the async
task.
https://bugzilla.gnome.org/show_bug.cgi?id=642652
st_theme_node_get_border_image() may return %NULL, leading to a
segfault in st_border_image_get_file() when glib is compiled with
G_DISABLE_CHECKS.
https://bugzilla.gnome.org/show_bug.cgi?id=780381
The built-in telepathy integration is far less prominent than it
used to be, and doesn't really justify a link time dependency to
send debug message over D-Bus.
https://bugzilla.gnome.org/show_bug.cgi?id=771721
We are still using DBUS_NAME_FLAG_REPLACE_EXISTING from dbus-glib
in some places (whose headers are drawn in via telepathy-glib).
As both GIO and dbus-glib use the values that will end up being
sent on the bus, the define and enum value are interchangeable,
but it's clearly better to consistently use the library that is
explicitly included.
https://bugzilla.gnome.org/show_bug.cgi?id=771721
Rename the signals which have been used to handle XDnd events to more inclusive
ones. So that these signals can be used to handle the DnD events in Wayland.
https://bugzilla.gnome.org/show_bug.cgi?id=765003
Mutter now provides versioned libraries and pkg-config files, meaning
an application using libmutter and friends need to depend on a specific
version of the API.
https://bugzilla.gnome.org/show_bug.cgi?id=777317
Solaris 11.3.5 and later have a Linux-compatible implementation of
/proc/self/cmdline, so the code to use it can be enabled in gnome-shell
on Solaris - if used on an older OS, it simply fails to open the file
and returns without doing anything, just as the code did before enabling
this.
https://bugzilla.gnome.org/show_bug.cgi?id=776199
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
It isn't useful to move the keyboard focus to a hidden actor, so
only include visible actors in the focus chain - this is in fact
the documented behavior of st_widget_get_focus_chain(), so having
the default implementation return all children has always been
unexpected.
https://bugzilla.gnome.org/show_bug.cgi?id=778158
This fixes the shell not picking updates to the contents of the underlying
.desktop files for application launchers, or when a .desktop file is
overriden by a user-installed one under ~/.local/share/applications
https://bugzilla.gnome.org/show_bug.cgi?id=773636
After having embedded a Gtk window, we start to listen for the
corresponding MetaWindow to know when it has been mapped by the
compositor. If the embedder does not realize the window immediately,
and some other window is created and mapped before the embedder
realizes the window, we would prior to this patch try to dereference
the not created GdkWindow. Fix this by NULL checking the GdkWindow
before dereferencing. We will never miss the needed MetaWindow creation
since it can not have been mapped have it not yet been realized.
https://bugzilla.gnome.org/show_bug.cgi?id=776130
This will be required in the upcoming version of GJS.
The reference count on ShellGlobal is 2 at this point, because JS holds a
reference due to the "window.global = Shell.Global.get()" line in
ui/environment.js. Therefore, destroy the GjsContext first, then unref
the ShellGlobal object.
Cleaning up ShellGlobal was previously only enabled behind a debug
environment variable, but it should be required now.
https://bugzilla.gnome.org/show_bug.cgi?id=775374
Sliced images are loaded into a group actor with one child actor
per slice. In case loading the image fails, we currently quietly
return the empty group actor, which makes diagnosing problems
unnecessarily hard - just be a bit more verbose on failure.
https://bugzilla.gnome.org/show_bug.cgi?id=774805
This might be a good fit for extension developers: With
this option one doesn't need to restart the whole Shell
in order to see their changes in effect.
https://bugzilla.gnome.org/show_bug.cgi?id=772593
And adapt existing callers to the new API. This will allow us to
implement a way to launch applications on the discrete GPU for systems
where an "Optimus" system exists.
https://bugzilla.gnome.org/show_bug.cgi?id=773117
You can define a new importer object by importing a subdirectory in GJS.
This is undocumented, but it is likely to at least hold until the whole
thing moves to ES6 modules, after which we'll be able to do this purely
in JS with Reflect.Loader.
Since this was the only thing the ShellJS library did, we can remove it
altogether.
This allows us to discontinue use of the gjs-internals-1.0 embedder API.
https://bugzilla.gnome.org/show_bug.cgi?id=772386
Our window matching currently fails frequently with Flatpak
applications, as one of the primary hints used to link windows
with .desktop files - the WM_CLASS - no longer matches when
flatpak renames the exported .desktop file. Worse, as Flatpak
applications are run in their own PID namespace, different
apps frequently share a common _NET_WM_PID, resulting in
unrelated apps being grouped together by one of the fallback
paths. To match Flatpak applications reliably, take the newly
exported Flatpak ID into account.
https://bugzilla.gnome.org/show_bug.cgi?id=772615
Other windows like the mutter Xwayland selection bridges might deal with
the clipboard, which would result in events visible on st-clipboard event
filters.
In order to avoid unintended results, ignore events that are not meant for
the clipboard window.
https://bugzilla.gnome.org/show_bug.cgi?id=760745
Mutter may capture the screen in multiple capture regions. If this is
done, take these images and composite them onto one large image, which
is then passed into the gstreamer source.
When clutter gives us multiple captures (multiple cairo_surface_t's),
composite them into one large image and use that as final screenshot
result. This makes screenshooting work when mutter uses multiple views.
https://bugzilla.gnome.org/show_bug.cgi?id=770128
