Skip focus tests in make check

These require a window manager to work, and we currently don't
run one when we run make check tests under Xvfb.
reftests: Make textview-margins pass in make check

I found that setting margins to zero makes the textview clip
away some overshooting pixels. So, instead of a 0/10 split,
do this test with a 2/8 split of margins, to avoid the clipping
issue.
GtkToolbar: Set clip

This allows outset box shadows to work on toolbars.

https://bugzilla.gnome.org/show_bug.cgi?id=734526
wayland: Remove overly complex cursor cache
Fix animation-direction reftest

This was another victim of clipping changes - the labels were
overdrawing each other, leading to test failure. Prevent this
by separating the grid columns.
Update DISTCHECK_CONFIGURE_ARGS

The --disable-rebuilds option does not exist anymore, so remove
it. At the same time, add --enable-installed-tests.
Fix reftests for builddir != srcdir

Make gtk-reftest consult the REFTEST_MODULE_DIR environment
variable to find out where to look for modules, and fix the
libtool hack to construct the .libs subdirectory correctly.
3.13.6
Bump version
treeview: Check the selected node active flag before maybe starting rubberband

This check used to be present in the pre-gestures code, but was unintentionally
removed when splitting code into drag/multiclick gestures. The policy used to
be that if clicking happened on an already selected node, DnD would happen
instead of rubberband selection, so this behavior is resuscitated.

https://bugzilla.gnome.org/show_bug.cgi?id=734143
Reconstruct a missing file

Sadly I had forgotten to add selectionmode.ui to git.
Here is a reconstructed version that seems to work.
widget-factory: Turn off focus-on-click for notification close button

... because that is what most applications are doing. So lets do the
same thing for the sake of consistency and setting a good example.

https://bugzilla.gnome.org/show_bug.cgi?id=734614
widget-factory: Add a reset button to the notification

Change the initial value to something that is not a multiple of 3, so
that dismissing the notification on reset makes sense. Let's use 50
because that is already being used elsewhere.

https://bugzilla.gnome.org/show_bug.cgi?id=734614
GtkSpinButton: Only notify 'adjustment' if the property changed

https://bugzilla.gnome.org/show_bug.cgi?id=734649
widget: Include event controllers' event mask on gtk_widget_get_events()

gtk_widget_get_events() must indeed tell about events enabled purely through
a GtkEventController, those events will most surely trigger event handlers.

https://bugzilla.gnome.org/show_bug.cgi?id=734357
stack: Ensure the bin window has an evmask suitable to windowless children

If a child has set_has_window == FALSE, it purely relies on the events set on
the parent window, for which the bin window used to just ensure the exposure
mask, eating all input events.

https://bugzilla.gnome.org/show_bug.cgi?id=734357
GtkIconHelper: Short circuit _gtk_icon_helper_get_size in some cases

_gtk_icon_helper_get_size() is often used during size request and may
not necessary mean that the icon will be displayed immediately. In
many common cases we know the size without having to ensure a surface.
In many cases this means we can avoid loading an icon until needed, and
in the case of stateless IconHelpers such as GtkCellRendererPixbuf this
is very important as otherwise it will constantly be reloading icons
if the displayed set is larger than the in-memory icon cache.

https://bugzilla.gnome.org/show_bug.cgi?id=734651
Change way alpha is used when recoloring symbolics

If the foreground color has an alpha != 1 we used to just pass that into
the svg. This is useful to e.g. render an insensitive icon. However,
that is not an ideal model for symbolics. For instance, if the icon uses
overlapping areas when drawing, expecting these to be opaque then the
transparent color will result in a different alpha value for the overlapping
area. Also, non-foreground symbolic colors are still rendered opaque, and
the recoloring of pngs can't handle transparent colors.

So, instead we extract any alpha from the foreground, render using the
opaque colors and then apply the foreground alpha to the entire result.
This means we get an even transparency, even for other colors, and we
can apply alpha for the pngs too.

https://bugzilla.gnome.org/show_bug.cgi?id=734668
Fix symbolic-icon-translucent-color reftest

When using the pre-rendered png symbolics it seems that we're off a
tiny bit in a few of the pixels on the antialiased borders of a
stroke. To fix this we switch the icon to media-playback-stop-symbolic
which has no such antialiased borders.

I don't quite understand why the pixels are off, this needs more
research.

https://bugzilla.gnome.org/show_bug.cgi?id=734668
wayland: Initialize cursor cache earlier

Without this, I was getting a crash because the theme change
function was trying to iterate over the hash table before
it was created.