I guess it's used for the lrelease call in the ebuild? That should be "$(qt4_get_bindir)"/lrelease instead (from qmake-utils).
commit 140e8d39442dd6cd411f2ec75265d73feae1ba73 Author: Mike Gilbert <floppym@gentoo.org> Date: Thu Oct 22 13:39:27 2015 -0400 net-p2p/transmission: Refer to lrelease by absolute path Bug: https://bugs.gentoo.org/563500 Package-Manager: portage-2.2.23_p4 net-p2p/transmission/transmission-2.84-r3.ebuild | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)