Instead of only doing a naive filesystem search, also run the linker
so that it can tell us whether the -F path specified actually contains
the framework we're looking for.
Unfortunately, `extraframework` searching is still not 100% correct in
the case when since we want to search in either /Library/Frameworks or
in /System/Library/Frameworks but not in both. The -Z flag disables
searching in those prefixes and would in theory allow this, but then
you cannot force the linker to look in those by manually adding -F
args, so that doesn't work.
This is a simple test case, checking for installed_files.txt, which just
makes sure the syntax is accepted.
Manual tests confirmed the permissions were set correctly.
A follow up commit adds a unit test based on this directory.
Nirbheek Chauhan
Jussi Pakkanen
Filipe Brandenburger