sys::Process: Add a SetWorkingDirectory method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140433 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Unix/Process.inc b/lib/Support/Unix/Process.inc
index 5cdb11c..da440fd 100644
--- a/lib/Support/Unix/Process.inc
+++ b/lib/Support/Unix/Process.inc
@@ -293,3 +293,7 @@
 const char *Process::ResetColor() {
   return "\033[0m";
 }
+
+void Process::SetWorkingDirectory(std::string Path) {
+  ::chdir(Path.c_str());
+}