[libcxx] [test] Fix fs.op.proximate for windows
Simmilar to many other similar path handling tests, convert the
test reference to preferred separators, and ifdef a few test references
that use network root names.
Additionally, generalize code for trimming off the root path for
generating relative_cwd, and for skipping the root name element
in count_path_elems.
Rename one fictive path for consistency with the other test cases,
and add a bunch of more test cases for completeness.
Differential Revision: https://reviews.llvm.org/D98988
GitOrigin-RevId: 695ec081a4a09d58796c8b410801d2cefce7580b
1 file changed
