[clang-tidy] Added a test -export-fixes with relative paths.
[clang-tidy] Added a test -export-fixes with relative paths.

Summary: A test for D51864.

Reviewers: ioeric, steveire

Reviewed By: steveire

Subscribers: xazax.hun, cfe-commits

Differential Revision: https://reviews.llvm.org/D51865

git-svn-id: a34e9779ed74578ad5922b3306b3d80a0c825546@347760 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra,llvm-mirror/clang-tools-extra