clang-format: Avoid bad line break.

Before:
  int
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaa(const
                                typename aaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa);

After:
  int aaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
      const typename aaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa);

llvm-svn: 215442