[clang-tidy] fix buildbot hicpp-signed-bitwise
[clang-tidy] fix buildbot hicpp-signed-bitwise

To finally fix the buildbot I added one single warning testcase.


git-svn-id: a34e9779ed74578ad5922b3306b3d80a0c825546@314816 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