[clang-tidy] Address post-commit comments

Summary:
Also add a test to verify clang-tidy only apply the first alternative
fix.

Reviewers: alexfh

Subscribers: xazax.hun, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D60857

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@358666 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed