Several small changes in formatting decisions.

1. Use a hanging ident for function calls nested in binary expressions.
   E.g.:
   int aaaaa = aaaaaaaaa && aaaaaaaaaa(
                                aaaaaaaaaa);

2. Slightly improve heuristic for builder type expressions and reduce
   penalty for breaking before "." and "->" in those.

3. Remove  mostly obsolete metric of decreasing indent level. This
   fixes: llvm.org/PR14931.

Changes #1 and #2 were necessary to keep tests passing after #3.