clang-format: [ObjC] Further improve wrapping of methods calls without inputs.

Before:
  [aaaaaaaaaaaaaaaaaaaaaaa
      .aaaaaaaa[aaaaaaaaaaaaaaaaaaaaa] aaaaaaaaaaaaaaaaaaaaaa];

After:
  [aaaaaaaaaaaaaaaaaaaaaaa.aaaaaaaa[aaaaaaaaaaaaaaaaaaaaa]
      aaaaaaaaaaaaaaaaaaaaaa];

llvm-svn: 237244