Fix clang-tidy test after r350714. NFC

llvm-svn: 350715

diff --git a/clang-tools-extra/test/clang-tidy/Inputs/mock-libcxx/bin/clang b/clang-tools-extra/test/clang-tidy/Inputs/mock-libcxx/bin/clang
new file mode 100644 (file)
index 0000000..ed34c1f
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/Inputs/mock-libcxx/bin/clang
@@ -0,0 +1 @@
+This file is a placeholder to keep its parent directory in git.