build: fix make check
This contains several fixes to the current tests:
- Remove glib mem profiler call from src/tests, which is known not to
work with the latest glib release:
https://bugzilla.gnome.org/show_bug.cgi?id=701694
valgrind could be used instead.
- Replace g_type_init() call in tests with ibus_init().
- Fix ibus-bus test after the DBus property change (commit
458945e7).
no global engine may be set in the test environment. Also add more
assertions to check the return values.
- Fix pygobject test to use LOG_COMPILER and move sys.path adjustment
into the test script itself.
- Add new files to po/POTFILES.in.
BUG=
R=takao.fujiwara1@gmail.com
Review URL: https://codereview.appspot.com/
11156043