tests: Re-wire the testgobject test program to the build system

After the build system rework in commit f9eb9e testgobject fell through
the cracks and was not built since then.

Re-enable it, even if it is currently failing due to commit 31fde56.

(Tweaked by Philip Withnall to add meson.build support.)

https://bugzilla.gnome.org/show_bug.cgi?id=701156

tests/gobject/Makefile.am

@@ -22,6 +22,7 @@ installed_test_programs = \
 	signals					\
 	singleton				\
 	references				\
+	testgobject				\
 	$(NULL)
 
 # Don't install these ones, and keep them out of 'make check' because they take too long...
@@ -43,6 +44,7 @@ accumulator_SOURCES = accumulator.c testmarshal.c testmarshal.h
 signals_SOURCES = signals.c
 defaultiface_SOURCES = defaultiface.c testmodule.c testmodule.h
 dynamictype_SOURCES = dynamictype.c testmodule.c testmodule.h
+testgobject_SOURCES = testgobject.c
 
 if ENABLE_TIMELOOP
 installed_test_programs += timeloop-closure

tests/gobject/meson.build

@@ -8,6 +8,7 @@ gobject_tests = [
   ['signals'],
   ['singleton'],
   ['references'],
+  ['testgobject'],
 ]
 
 # We cannot use gnome.genmarshal() here