the localrc is really just executable shell, which means there are
tons of edgecases where you can't treat it the same as simple
assignment a=b.
Instead of trying to be smart about things and reduce duplication in
the localrc files, just do the naive thing and stack up all the shell
declarations in order. When evaluated in shell they will end up
stacking up as expected.
Change-Id: I231d130b24b02cdd79618f85472cee21905884e0
de46354ed3