The "multiple plugins loaded at once" strategy was always a big fiction:
while it may be viable if you're super careful, it's fragile and requires
a bit of infrastructure that we would be better off without.
Note that for simplicity, we're keeping the MetaPluginManager, but it only
manages one plugin. A possible future cleanup would be to remove it entirely.
https://bugzilla.gnome.org/show_bug.cgi?id=676855
We already check that the plugin has the appropriate vfunc in the klass
structure, so we shouldn't need to check for the same data again with
a "features" long.
https://bugzilla.gnome.org/show_bug.cgi?id=676855
Mutter originally started out with the idea that only a subset of the total
API was exposed to plugins, so some APIs are duplicated on MutterPlugin.
We've long since abandoned that idea; remove these wrappers.
https://bugzilla.gnome.org/show_bug.cgi?id=671103
If mutter is going to be a "real" library, then it should install its
includes so that users can do
#include <meta/display.h>
rather than
#include <display.h>
So rename the includedir accordingly, move src/include to src/meta,
and fix up all internal references.
There were a handful of header files in src/include that were not
installed; this appears to have been part of a plan to keep core/,
ui/, and compositor/ from looking at each others' private includes,
but that wasn't really working anyway. So move all non-installed
headers back into core/ or ui/.
https://bugzilla.gnome.org/show_bug.cgi?id=643959
