The methods Utils::UnixUtils::fileBrowser and
Utils::UnixUtils::substituteFileBrowserParameters are both declared when
compiling on MacOS, but their implementation is not compiled into
libutils. So this gives linker errors.

Change-Id: I0befb607dda0a83d681068f8236167ba88918460
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>