[clang-tidy] Fix a potential infinite loop in readability-isolate-declaration check.

Reviewers: ilya-biryukov

Subscribers: xazax.hun, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67654

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@372206 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed