MesonDep1 doesn't use symbols from MesonDep2, but uses the MesonDep2
structure definition (so it only needs the header). This means only
generate_gir needs a dependency on MesonDep2 and shared_library doesn't.
This was broken earlier.
MesonSample uses symbols from MesonDep1 and MesonDep2, so both the
library and the gir get a dependency on MesonDep1, and on MesonDep2
(transitively). The transitive dependency was broken earlier.
Instead of using a whitelist, use a blacklist. Also print a more useful
error if the regex fails to match.
Use an underscore in the gir test to trigger this.
Fixes#436
print->print_message is caused because GI does print->print_
in python bindings which is not good.
Signed-off-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>