We have been ignoring those buttons since 3.16 after they had been
broken in the default theme for a couple of versions. As nobody
appears to miss them, it's time to remove them for good.
Displaying all Wayland windows with the XID of 0x0 makes it hard
to figure out what is going on ... use the recently-added
window->stamp to show Wayland windows as W1/W2/W3...
This commits refactors cursor handling code and plugs in logic so that
cursor sprites changes appearance as it moves across the screen.
Renderers are adapted to handle the necessary functionality.
The logic for changing the cursor sprite appearance is done outside of
MetaCursorSprite, and actually where depends on what type of cursor it
is. In mutter we now have two types of cursors that may have their
appearance changed:
- Themed cursors (aka root cursors)
- wl_surface cursors
Themed cursors are created by MetaScreen and when created, when
applicable(*), it will extend the cursor via connecting to a signal
which is emitted everytime the cursor is moved. The signal handler will
calculate the expected scale given the monitor it is on and reload the
theme in a correct size when needed.
wl_surface cursors are created when a wl_surface is assigned the
"cursor" role, i.e. when a client calls wl_pointer.set_cursor. A
cursor role object is created which is connected to the cursor object
by the position signal, and will set a correct texture scale given what
monitor the cursor is on and what scale the wl_surface's active buffer
is in. It will also push new buffers to the same to the cursor object
when new ones are committed to the surface.
This commit also makes texture loading lazy, since the renderer doesn't
calculate a rectangle when the cursor position changes.
The native backend is refactored to be triple-buffered; see the comment
in meta-cursor-renderer-native.c for further explanations.
* when we are running as a Wayland compositor
https://bugzilla.gnome.org/show_bug.cgi?id=744932
Before, it used to be in the screen, but now,
meta_cursor_reference_from_theme can never fail. Move it to where we
load the images from the cursor name.
This was introduced in commit c6793d477a
to prevent window self-maximisation. It turns out that that bug seems
to have been fixed meanwhile in a different way since the reproducer
in https://bugzilla.gnome.org/show_bug.cgi?id=461927#c37 now works
fine with this special handling removed.
In fact, failing to set window->fullscreen immediately when loading
the initial set of X properties causes us to create a UI frame for a
window that sets _NET_WM_STATE_FULLSCREEN.
This, in turn, might cause the fullscreen constrain code to fail if
the window also sets min_width/min_height size hints to be the monitor
size since the UI frame size added to those makes the rectangle too
big to fit the monitor. If the window doesn't set these hints, we
fullscreen it but the window will get sized such that the UI frame is
taken into account while it really shouldn't (see the reproducer
above).
https://bugzilla.gnome.org/show_bug.cgi?id=753020
Since commit 14b0a83f64 we store the
main window monitor instead of computing it every time. This means
that we must now ensure that it's updated before trying to use it
which we do from meta_screen_resize_func() or else we'll crash on an
assertion later on when removing a monitor:
assertion failed: (which_monitor < workspace->screen->n_monitor_infos)
https://bugzilla.gnome.org/show_bug.cgi?id=752674
They otherwise fall through paths that enable bypass_clutter, this
is necessary so they can be picked by captured-event handlers
along the actor hierarchy.
https://bugzilla.gnome.org/show_bug.cgi?id=752248
Since we scale surface actors given what main output their toplevel
window is on, also scale the window geometry coordinates and sizes
(window->rect size and window->custom_frame_extents.top/left) in order
to make the window geometry represent what is being rendered on the
stage.
https://bugzilla.gnome.org/show_bug.cgi?id=744934
The main monitor of a window is maintained as 'window->monitor' and is
updated when the window is resized or moved. Lets avoid calculating it
every time it`s needed.
https://bugzilla.gnome.org/show_bug.cgi?id=744934
A much less hacky version of maximize / unmaximize is reimplemented
in terms of this, but it could also eventually be used for fullscreen /
unfullscreen, and tile / untile.
The only time we ever execute this code is when we're minimizing or
hiding a window, in which case we should respect stacking order.
This fixes weird "bugs" where windows from the same app magically pop up
over other windows.
This is an extremely niche feature, and conflicts with the rest of our
interface being consistent about not allowing resizing while tiled or
maximized.
A window may be hidden even if not minimized itself, for instance
when an ancestor is minimized. As meta_window_focus() will refuse
to actually focus the window in that case, don't pick it in the first
place.
https://bugzilla.gnome.org/show_bug.cgi?id=751715
Going from fullscreen to unfullscreen involves a frame border size, so
in order to properly interpret the saved rect size, we need to make sure
that the frame borders are fully up to date.
The "calc showing" operation is queued in a few places alongside MetaWindow
creation, we should be ignoring these until there is a buffer to show.
https://bugzilla.gnome.org/show_bug.cgi?id=750552
window->is_alive isn't initialized explicitly so it defaults to FALSE
meaning that if the first ping fails we'd short circuit and not show
the delete dialog as we should.
We could initialize the variable to TRUE but in fact we don't even
need the variable at all since our dialog management is enough to
manage all the state we need, i.e. we're only interested in knowing
whether we're already displaying a delete dialog.
This does change our behavior here since previously we wouldn't
display the dialog again if the next ping failed after the dialog is
dismissed but this was arguably a bug too since in that case there
wouldn't be a way to kill the window after waiting for a while and the
window kept being unresponsive.
https://bugzilla.gnome.org/show_bug.cgi?id=749711
When running as an X11 compositor we do this for every event we see on
the X event stream. As a wayland compositor we don't go through that
code path but since we see all events we can easily do this on motion
events.
In fact, we don't even need this caching when we're a wayland
compositor since we can always find where the pointer is without a
round trip but we're sharing the current monitor logic with the X
path so let's keep it as is for now.
https://bugzilla.gnome.org/show_bug.cgi?id=748478
The existing private get_monitor_neighbor() function returns a
MetaMonitorInfo, which is private as well. Add a public wrapper
that returns a monitor index instead, as we do for other public
monitor-related methods.
https://bugzilla.gnome.org/show_bug.cgi?id=633994
Since the frame is the window that's redirected, there's no reason for
it to match the root window. There *is*, however, a big incentive to
match the window's visual, since not doing so might trigger automatic
redirection.
On a specific platform, we construct a depth-32 root window, and stick a
depth-24 child window inside it. The frame ends up being created
depth-32, not depth-24, so we get automatic redirection.
clutter currently never emits activated or deactivated signals on
the stage object when using the EGL backend. Since the stage never
gets activated, accessibility tools, like orca, don't work.
This commit makes mutter take on the responsibility, by tracking
when the stage gains/loses focus, and then synthesizing stage
CLUTTER_STAGE_STATE_ACTIVATED state events.
A limitation of this approach is that clutter's own notion of
the stage activeness won't reflect mutter's notion of the
stage activeness. This isn't a problem, in practice, and can
be addressed in the medium-term after making changes to
clutter.
https://bugzilla.gnome.org/show_bug.cgi?id=746670
With all input events being handled through clutter, this only confuses
things, and most nominally, coerces touch events through places we didn't
intend to, like the window frame.
This makes again all touch events only handled in the passive grab on X11,
while the rest stays pointer (emulated) only.
https://bugzilla.gnome.org/show_bug.cgi?id=745335
In order to switch to the correct surface actor scale given the monitor
the surface is on, without relying on the client committing a new state
given some other side effect, sync the surface actor state when the main
monitor associated with the corresponding window changed.
https://bugzilla.gnome.org/show_bug.cgi?id=744933
This just exposes the type and the singleton getter necessary to make
it available to introspection. We'll expose more functionality as it
becomes needed.
https://bugzilla.gnome.org/show_bug.cgi?id=743745
We're locked to frame sync anyway, so it doesn't make sense to try to
redraw early. In casual testing, this seems to actually make things
faster, as well.
When looking for space to place a new window, other non-minimized
windows on the same workspace should be taken into account. However
the current check does not work correctly when the placed window is
located on all workspaces, so handle that case explicitly.
https://bugzilla.gnome.org/show_bug.cgi?id=743217
When running as a dispay server pointer barriers are a server side
feature and requires no client interaction of any sort. This patch
implements pointer barriers that can be used when running as a display
server on the native backend. Running as a display server using the X11
backend is currently not supported.
https://bugzilla.gnome.org/show_bug.cgi?id=706655
This patch removes the X11 specific code from MetaBarrier and creates an
abstraction layer MetaBarrierImpl. The existing X11 implementation is
moved to a new GObject MetaBarrierImplX11 implementing the abstract
interface MetaBarrierImpl which is instantiated by MetaBarrier when
supported.
While at it, move it to backends/ and properly name the files.
https://bugzilla.gnome.org/show_bug.cgi?id=706655
MetaKeyCombo is about the *unresolved* keybinding, which can either be a
"keysym" (<Ctrl>F) or a "keycode" (<Ctrl>0x21). When we resolved the
keysym to a keycode, we stuffed it back in the same MetaKeyCombo, which
confused about what the "keycode" field was for. Thus, we often stomped
on the user's explicit choice if they chose a keycode binding value.
To solve this, create a separate structure, the "devirtualized key combo"
or MetaKeyDevirtCombo, which contains a resolved keycode from the
keysym, and a devirtualized modifier mask. The MetaKeyCombo is now
always a "source" value, and the MetaKeyDevirtCombo is now always what
the user chose.
This also lets us significantly clean up the overlay and ISO key binding
paths.
The reason MetaKeyCombo has a keycode value at all is *not* to store the
devirtualized keycode from the keysym, but instead to allow people that
type in "0x55" into the preference. Everything except the overlay-key
respected this. Make the overlay-key binding respect this.
Break down the beautiful core/ui abstraction barrier by inserting
a pointer to MetaWindow into a MetaUIFrame. I'm a scoundrel, I know.
We'll use this very soon to destroy meta_core_get.
Rest in peace you magnificent format, love-child of arcane X11 drawing
API and markup craze, you will not be missed.
We do remember however the bravery of a many men and women, who fearlessly
descended into the guts of your intrinsics and turned ugliness into beauty;
their work will still be spoken of when you will long have been forgotten.
https://bugzilla.gnome.org/show_bug.cgi?id=741917
This reverts commit ec8ed1dbb0.
1) It turns out to add a momentary flicker from the transition
between the login screen and user session
2) It actually isn't needed anymore since bug 733026
https://bugzilla.gnome.org/show_bug.cgi?id=740377
The set/unset branches of meta_display_update_pointer_emulating_sequence()
have been split and put directly where it makes sense. The pointer emulated
sequence will be updated before processing the CLUTTER_TOUCH_BEGIN, and
after processing the CLUTTER_TOUCH_END, this way the checks on this hold
true during all the sequence lifetime.
https://bugzilla.gnome.org/show_bug.cgi?id=738411
Returning FALSE here gets the button release event propagated to the
client on wayland, which is unexpected after xdg_surface.move/resize()
have been called.
https://bugzilla.gnome.org/show_bug.cgi?id=738888
Commit 2f9c601 accidentally changed the logic here, changing the grab
behavior when not using raise-on-click. Fix this.
Spotted-by: Adam Goode <adam@spicenitz.org>
Fullscreen windows look weird when they are overlapped by system chrome,
which currently happens when another window is stacked above. We used to
auto-minimize fullscreen windows in that case, which proved to be both
unreliable and unpopular. So instead, keep the system chrome hidden even
when the fullscreen window is not stacked at the top.
https://bugzilla.gnome.org/show_bug.cgi?id=693991
The constructor would collect windows that are sticky before initializing its state
which would lead to a crash in the case of windows with struts which trigger a work
area recalculation where mutter would assume, due to uninitialized state, that an
existing work area has to be freed.
https://bugzilla.gnome.org/show_bug.cgi?id=738384
There's a small window before a window that is being unmanaged is
unregistered with the display. The MetaScreen::window-left-monitor
and MetaWorkspace::window-removed emissions fall right into that
window, so code that runs in that time may well be out of our
control; we can make sure that the method it can use to get an
updated list of windows no longer contains the destroyed window
though, which is a much better option than expecting everyone to
filter the list themselves.
In Wayland, popup window types are not override-redirect, and thus can
steal window focus away from their parent window when clicked on.
This means that we need to make sure their appearance is properly
propagated to the parent windows so the parent windows don't lose their
focus while they're propagated.
Since we now directly expose the reverses bindings directly, we
don't have to have this special-case in do_choose_window.
More importantly, if the backwards binding is pressed and has the Shift
key included, this will actually revert it
This doesn't matter for Alt-Tab in gnome-shell, which already replaces
it with a better Alt-Tab replacement, but it does matter for Alt-Esc,
which switches between windows directly.
Windows are relocated before their workspace is removed, however this
is only necessary for windows that are *only* on that workspace; for
windows on all workspaces, that step is annoying as it will unset the
sticky state requested by the user.
https://bugzilla.gnome.org/show_bug.cgi?id=737625
The workspace MRU lists are updated when windows are managed/unmanaged
or change workspaces. However those updates obviously only apply to
existing workspaces - new workspaces will always start out with an empty
MRU list, despite sticky windows already being "on" that workspace.
As we now assert that the list contains all windows located on the
workspace, we need to initialize it correctly to avoid a crash.
https://bugzilla.gnome.org/show_bug.cgi?id=737581
We only grant requests to set the demands-attention hint if the window
is at least partially obscured; so for non-minimized windows on the
active workspace, we check if any other window on the same workspace
that is higher in the stack overlaps.
However in the case of a sticky window, window->workspace is NULL, so
we end up considering any non-sticky window on a different workspace.
At this point we have already established that the window is showing
on the active workspace, so use that to filter for windows that may
overlap.
Since the introduction of set_workspace_state(), window->workspace
will always be NULL when on_all_workspaces is set - passing that
to a workspace function that does not validate its input will then
result in a crash.
Use the get_workspace() function instead, which will always return
a valid workspace.
Since commit 2eec11b445, windows without a __NET_WM_DESKTOP property
that should be on all workspaces are not added to the active workspace;
this is correct, however not adding them to any workspace is not ...
set_workspace_state () returns early when the desired sticky state
and workspace match the current property values, assuming that the
corresponding MRU lists are already correct in that case.
However that might not be the case when we are setting the initial
state, so don't take the shortcut in that case.
https://bugzilla.gnome.org/show_bug.cgi?id=737178
A window may either be sticky because it has been requested as such,
or because it is placed on a non-primary monitor (and the corresponding
preference is set). While we do take the latter into account, we
currently override the sticky state later during initialization;
be a bit more careful there to get the initial state right.
https://bugzilla.gnome.org/show_bug.cgi?id=737178
Commit 1af0033368 made a subtle change
regarding how XKeysymToKeycode behaves. It does a depth first search
while XKeysymToKeycode is documented to do a breadth first search:
"this function looks in each column of the core keyboard mapping in
turn and returns the lowest numbered key that matches in the lowest
numbered group" - from the XKB library documentation
Looping over all keycodes for each layout and level index makes us go
back to the previous behavior.
https://bugzilla.gnome.org/show_bug.cgi?id=737134
With the change to how hidden windows are stacked, the position
of the guard window with respect to the hidden windows got flipped
and the guard window was at the bottom of everything; fix it to
be on top of the hidden windows.
https://bugzilla.gnome.org/show_bug.cgi?id=737233
Commit 2f229c3928 removed the code to compute the above-tab
keycode and replaced it with a simple constant from linux/input.h.
We obviously cannot depend on linux headers on non-linux systems,
so provide a fallback definition in that case (which is expected
to work assuming the system is using the Xorg xf86-input-keyboard
driver).
https://bugzilla.gnome.org/show_bug.cgi?id=737135
The titlebar rect is in window coordinates, while screen regions are
obviously not. Fix by translating into screen coordinates before
testing for overlaps.
https://bugzilla.gnome.org/show_bug.cgi?id=736915
Going through GSD's settings was done in context of patches that
did not land; it is simpler and more consistent with GTK+ to use
the corresponding XSetting instead.
Restacking the frame for a window while unmanaging the window is
harmless, but for undecorated (in particular, client-side-decorated)
windows, this causes problems because the window is typically
destroyed by the client immediately after withredrawing the window.
Skip windows flagged as being unmanaged when assembling the new
stack and when comparing the old order to the new stack.
Add a stacking test for this.
We shouldn't scale the cursor size in mutter we g-s-d exports
the correct size on hidpi so use gtk-cursor-theme-size.
This way we also catch changes on resolution updates.
https://bugzilla.gnome.org/show_bug.cgi?id=729337
This reverts commit 4fe66ce0a9.
This is wrong ... we should not scale the cursor size but read
the cursor xsettings that gets exported by gsd. Also this won't update on
resolution changes.
https://bugzilla.gnome.org/show_bug.cgi?id=729337
When restacking the last window alone, we would trigger this off-by-one
error. This would throw us off the end of the array, causing lower_below
warnings for nonsensical values.
Since the last window already is lowered below everything else, we
shouldn't need to lower it.
We have a quite accurate view of the X stack, so there's no good reason to ask
the X server to do restacking that has no effect. (Restackings that have no
effect on either X windows or Wayland windows were generally optimized out in
the synchronization code, but in other cases like moving an X window that is
only beneath Wayland windows to the top of the stack we would make such
requests.)
Removing such requests:
- Is a small efficiency win in itself
- Allows us to immediately go ahead and apply Wayland changes to the verified stack
- Prevents queued Wayland changes piling up waiting for an X event that will never
be received, since the X server will not send confirmation of no-op restacks.
Since such operations may still have an effect on the relative stacking of X
and Wayland windows, we need to continue applying them to the local stack.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Now that all actual stack shuffle is handled inside stack-tracker.c, we can make
meta_stack_tracker_record_[raise_above/lower_below] internal to that file and
remove the unused meta_stack_tracker_record_lower().
https://bugzilla.gnome.org/show_bug.cgi?id=736559
stack.c:sync_stack_to_xserver had both code for assembling the desired stack, and
code for enforcing the desired stack on the actual stack of X and Wayland windows;
the latter part is properly the domain of stack-tracker.c; moving the code to
apply the stack there both simplifies it and keeps stack.c more manageable.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
There was still code in stack.c to handle skipping override-redirect windows,
but since quite a while ago, meta_stack_add() is not called for OR windows
since they are outside our stacking control. Add an assertion and remove
unnecessary code.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
stack.c kept it's own record of the last stacking it requested, so that
restacking could be done with minimal moves, but we already have a better
view of the stacking order with the stack tracker, so use that instead.
This allows eliminating the special case for the first restack.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Since MetaStackTracker is the code that knows about the current X stacking order
and the relationship between X windows and Wayland windows, it's cleaner to
encapsulate stack manipulation in MetaStackTracker rather than have the calling
code make the X calls and only call into MetaStackTracker to inform it about
the changes.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
The step where we requery the stacking order from the server than combine
it in an arbitrary fashion with Wayland windows can be eliminated by observing
that we are the final authority for Wayland window stacking - so if we
apply each X event that we receive from the X server to our stack in a
way that leaves the X windows ordered in the same way as on the server,
and apply events that we have stored locally in a way that doesn't affect
the ordering of X windows, than we have a fully correct ordering of windows.
Ordering this in the order of first applying the X event and then applying the
local portion also means that as long as we had an up-to-date view of the X
stack the composite operation will be identical to what was requested.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Putting X windows and pointers to MetaWindows into a union had a number of
problems:
- It caused awkward initialization and conditionalization
- There was no way to refer to Wayland windows (represented by
MetaWindow *) in the past, which is necessary for the MetaStackTracker
algorithms
- We never even cleaned up old MetaStackWindow so there could be
records in MetaStackWindow pointing to freed MetaWindow.
Replace MetaStackWindow with a 64-bit "stack ID" which is:
- The XID for X Windows
- a "window stamp" for Wayland windows - window stamps are assigned
for all MetaWindow and are unique across the life of the process.
https://bugzilla.gnome.org/show_bug.cgi?id=736559
Add a private hook for the test framework to get XSyncAlarmEvent events -
this will be used to implement XSyncCounter based synchronization
so that the test framework can deterministically wait until Mutter
has seen actions performed by an X11 client.
https://bugzilla.gnome.org/show_bug.cgi?id=736505
Setting the scaling factor immediately after calling clutter_init()
avoids creating the stage at one size, then later resizing it to
a different size.
https://bugzilla.gnome.org/show_bug.cgi?id=736279
We can enter weird states where get_default_window is called during
window unmanagement, before the window has been fully removed from
the stack. Make sure these windows are *never* returned from
get_default_window, as focusing them can cause an assertion fail,
or worse.
Clutter events include the layout index codified into modifier_state,
unlike XI2 device events, which means that we need to mask it out so
that we can match successfully.
A lot of applications assume that the window is fully positioned when it
gets the MapNotify, especially simple applications. Make sure that the
window is only mapped through the calc_showing logic.
O-R windows appear in workspace->windows, which aren't relocatable,
so we can't simply check if the workspace is empty after relocating
all normal windows, since those windows remain.
Make sure that the only windows we have are those that are
on_all_workspaces.
This is bad behavior, and can also cause us to get in an infinite loop
if an OR window is mapped and unmapped in quick succession. This
sequence causes a MapNotify followed by an UnmapNotify, and when
processing the events, we'll call XMapWindow, XUnmapWindow, which will
put another set of MapNotify, UnmapNotify events in our queue, which we
then process by calling XMapWindow, XUnmapWindow, and so it goes
forever, or at least some scheduler uncorks us by making us call
XMapWindow when the window is already mapped, or XUnmapWindow when the
window is already unmapped.
We can stop this madness by simply making sure never to call neither
XMapWindow or XUnmapWindow on OR windows, which is the correct thing to
do anyway.
We commonly used the generic, undetailed signal 'changed' to track
changes to preferences. Since we crash on unknown preference types,
this can be dangerous if somebody adds a new setting that has a
type we're unfamiliar with, and something else changes it.
Instead of crashing, just fizzle out doing nothing.
In gnome-shell, we have a feature where the user can unmaximize windows
by dragging them from the panel above the window. With accurate
anchoring, this looks really weird as the cursor is now "detached" from
the window. Detect this case and put the cursor in the middle of the
window titlebar instead.
This seems to be more accurate with what we currently see in
GNOME. Without having the app expose this information to us, it might be
a better idea to use the default frame style for this information instead.
The cursor was anchored wrongly when trying to unmaximize windows from
dragging them from the top of the screen because of a few think-o's and
some code that forgot to be updated when we moved to the frame rect
coordinate system.
The cursor is still offset for windows that start dragging from the top
panel. This is technically correct, but looks wrong. We'll fix this in
the next commit.
The initialization sequence before was quite icky, initializing Clutter
in a few different places depending on what was going on.
Put that all back into main.c
This removes our Xwayland dependency in the native path. The direct
grabs are still there for the X11 backend and are a bit disgusting,
but that's OK. We can refactor it out later.
This introduces some pretty lousy hackery because it depends on
https://github.com/xkbcommon/libxkbcommon/pull/10 , and I really
don't want to wait on that to squash this dep.
Now that the internal mutter bindings and gnome-shell stopped using
META_KEY_BINDING_REVERSES, and after moving the 'adding shift reverses
the keybinding action' logic to gnome-control-center, we can remove
META_KEY_BINDING_REVERSES from mutter.
Plugin API is broken as this constant is removed from the exported
headers. ABI is broken as using this flag is now a noop.
https://bugzilla.gnome.org/show_bug.cgi?id=732385
Currently the bindings for {switch,cycle}.* actions are created with the
META_KEY_BINDING_REVERSES flag so that <shift>+binding triggers the
reverse action. However, gnome-control-center does not know about this
kind of implicit bindings, and, for example, cannot warn when the user
tries to setup a conflicting <shift>+xxx binding.
These backward <shift> bindings are being explicitly set in
gsettings-desktop-schemas, so the META_KEY_BINDING_REVERSES annotation
can be removed for them from mutter.
https://bugzilla.gnome.org/show_bug.cgi?id=732385
MetaKeyBinding can be marked as being reversed
(META_KEY_BINDING_IS_REVERSED), but MetaKeyHandlerFunc callbacks
cannot check whether this flag was set or not on the MetaKeyBinding
which triggered the callback.
https://bugzilla.gnome.org/show_bug.cgi?id=732295
The existing workspace management code is quite hairy, with plenty of
logic inline in all of window.c, workspace.c, and screen.c, making it
hard to understand or make changes to, since you might forget to change
several of the other places the code was around.
Rewrite the internal workspace management logic so that it's
centralized and all in window.c. Document the invariants we need to
maintain, and ensure that these invariants are properly kept, with
asserts in various places.
Extensive testing on gnome-shell did not bring up any issues, and this
is a considerable cleanup.
This will be used to replace some of the hooks that are used to call
into window.c, so that the workspace index property is properly kept up
to date.
We can't name the property "index" since it causes conflicts with the
meta_workspace_index method. This should really be called
meta_workspace_get_index, but oh well.
