clang-format: Fix ObjC method expr in binary expressions.

Before:
  bool a = ([aaaaaaaa aaaaa] == aaaaaaaaaaaaaaaaa || [aaaaaaaa aaaaa] ==
                                                         aaaaaaaaaaaaaaaaaaaa);

After:
  bool a = ([aaaaaaaa aaaaa] == aaaaaaaaaaaaaaaaa ||
            [aaaaaaaa aaaaa] == aaaaaaaaaaaaaaaaaaaa);

This fixes llvm.org/PR18271.

llvm-svn: 197552