The old files (DATADIR/component_name/file.rc) can still be loaded,
and a runtime warning is shown in such a case, telling people to install
into KXMLGUI_INSTALL_DIR (ECM patch posted to k-f-d)

This keeps DATADIR slightly cleaner, getting rid of many application subdirs
that would just contain a rc file. Some people seem to care about the cleanliness
of their DATADIR :-)

REVIEW: 119142