* src/tgba/tgbamask.hh (build_tgba_mask_acc_ignore): New function.
(tgba_mask::wanted): Take an acc argument.
* src/tgba/tgbamask.cc: Implement the above.
* src/tgbatest/maskacc.cc, src/tgbatest/maskacc.test: New files.
* src/tgbatest/Makefile.am: Add them.