As of 1.4, ClutterGLXTexturePixmap is identical to
ClutterX11TexturePixmap (with the differences having been moved into
the cogl layer). So make ShellGtkEmbed use the (introspected) X11
version, which then allows us to make the instance and class structs
public as well.
https://bugzilla.gnome.org/show_bug.cgi?id=608869
* Rename ShellGtkWindowActor to ShellGtkEmbed, and make it require
a ShellEmbeddedWindow rather than a general GtkWindow.
* Add ShellEmbeddedWindow subclass of GtkWindow that bypasses most
of the GtkWindow complexity for size negotiation, and calls out
to a clutter actor instead; also automatically handle reparenting
the GtkWindow into the stage window.
* Use the reworked ShellGtkEmbed in ShellTrayManager, this simplifies
the code a bit, and more importantly results in the tray icons
having the correct size negotiation, rather than having a fixed
24x24 size.
http://bugzilla.gnome.org/show_bug.cgi?id=580047
