Add a convenience createUniqueDirectory function.

There are a few valid situation where we care about the structure inside a
directory, but not about the directory itself. A simple example is for unit
testing directory traversal.

PathV1 had a function like this, add one to V2 and port existing users of the
created temp file and delete it hack to using it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185059 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/Support/FileOutputBufferTest.cpp b/unittests/Support/FileOutputBufferTest.cpp
index c7ca1ab..5e87319 100644
--- a/unittests/Support/FileOutputBufferTest.cpp
+++ b/unittests/Support/FileOutputBufferTest.cpp
@@ -30,12 +30,8 @@
   // Create unique temporary directory for these tests
   SmallString<128> TestDirectory;
   {
-    int fd;
     ASSERT_NO_ERROR(
-      fs::unique_file("FileOutputBuffer-test-%%-%%-%%-%%/dir", fd,
-                      TestDirectory));
-    ::close(fd);
-    TestDirectory = path::parent_path(TestDirectory);
+        fs::createUniqueDirectory("FileOutputBuffer-test", TestDirectory));
   }
 
   // TEST 1: Verify commit case.
diff --git a/unittests/Support/Path.cpp b/unittests/Support/Path.cpp
index d5591ea..ce335cc 100644
--- a/unittests/Support/Path.cpp
+++ b/unittests/Support/Path.cpp
@@ -147,13 +147,9 @@
   SmallString<128> TestDirectory;
 
   virtual void SetUp() {
-    int fd;
     ASSERT_NO_ERROR(
-      fs::unique_file("file-system-test-%%-%%-%%-%%/test-directory.anchor", fd,
-                      TestDirectory));
+        fs::createUniqueDirectory("file-system-test", TestDirectory));
     // We don't care about this specific file.
-    ::close(fd);
-    TestDirectory = path::parent_path(TestDirectory);
     errs() << "Test Directory: " << TestDirectory << '\n';
     errs().flush();
   }