Add a regression test for sessionrc parsing, handing and writing. The
test work in the following way: GIMP starts so that sessionrc is
deserialized and stored internally, the UI is shown, and then the
internal data structure about windows is serialized to a new
sessionrc. The test makes sure that a new sessionrc actually has been
created, and then that the content of the new file is identical to the
old one.
The WM tests mess up the GIMP dir, in particular any sessionrc if it
exists, due to the interface never being shown. Make the WM test use a
tmp dir to avoid that.
* tests.[ch]: initialize base so we have a tile cache and add
parameter "gboolean use_cpu_accel" so we can test stuff both with
and without using CPU features.
* tests/test-layer-grouping.c: changed accordingly. Call g_thread_init()
so the tile cache works (and to be on the safe side in general).
Enable us to have regression testing by introducing a core testing
framework that uses the GLib JUnit-like test library.
Do this by adding a new subdir app/tests that will contain all our
tests (it contains one trivial test already). Also add app/tests.[ch]
with a new function gimp_init_for_testing() so that test cases can
easily setup the core object system.