[PATCH] Unify handling of PWD (clang patch)

[Rafael Espíndola]

> +// RUN: cd %t/abc/def2
>  // RUN: not env PWD="%t/abc/def" clang-check "ijk/qwe/test.cpp" 2>&1 | FileCheck %s
>
> ----------------
> Just so this is more like reality, I'd use abc/def2 as the PWD.

One of the tests does "cd directory", the other does "cd symlink".
That way we test that we alway use PWD.

Cheers,
Rafael