notebook: correctly define the header region

Correctly define the header region to only be the area under the
tabs.
notebook: add style classes for orientation to the header
notebook: inform the theme to draw borders when requested

When the show-border property is TRUE ask the theme to draw
borders on the notebook header.
Improve doc of gtk_style_context_invalidate()

https://bugzilla.gnome.org/show_bug.cgi?id=708583
testsuite: Remove extra calls to gtk_style_context_invalidate()

They aren't needed anymore.
texthandle: Use the parent widget's style context

... instead of creating our own.
tests: Don't call gtk_style_context_invalidate()

It's not needed anymore.
stylecontext: Deprecate gtk_style_context_invalidate()

Everything is invalidated automatically these days.
icontheme: Use rgba() when loading symbolic icons

This way, we correctly pass on translucency information. Note: This
currently requires librsvg master.
reftests: Add a test for the symbolic color fix
testgtk: Remove idle test

The test is broken, written like it's 1999 and testing a feature that
I'm about to deprecate.
container: Deprecate resize mode

Resize modes don't work anymore, both because nobody ever uses them and
because the frame clock changed the way things work quite a bit. So we
don't want to advertise them as a good idea.

https://bugzilla.gnome.org/show_bug.cgi?id=708787
icontheme: Use gdk_rgba_to_string()

This gives us valid CSS. And now that librsvg parses valid CSS, that's a
fine thing to use.

And it fixes the problem where %g is locale-dependent.
Fix dark theme issues in the print dialog

The dimensions in the n-up illustration were not using the
color of the style for drawing.

https://bugzilla.gnome.org/show_bug.cgi?id=709420
csd: properly check titlebar visibility

Now that we are using child-visible to hide titlebars, we need to
adjust the visibility checks in various places to take it into account.

https://bugzilla.gnome.org/show_bug.cgi?id=709323
GtkWindow: Override gtk_container_remove ()

Check which child is being removed, title_box or the GtkBin child.

https://bugzilla.gnome.org/show_bug.cgi?id=709049
csd: add style classes for tiled and maximized

This lets us change the border radius when the window is
in one of these states.

https://bugzilla.gnome.org/show_bug.cgi?id=709215
csd: Keep a maximized flag

This mirrors what we do for fullscreen and tiled.
Adjust expected output of a11y tests

This is belatedly updating the tests after
5315661721137c1f195fa88c2bf12f1a3e32ecfa
Reorder message in configure.ac to display result on the same line

https://bugzilla.gnome.org/show_bug.cgi?id=341146

Signed-off-by: Timothy Arceri <t_arceri@yahoo.com.au>