Reduce penalty for breaks after "(" for functions with parameters.

Before:
  aaaaaaaaaaaaaaaaa(aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa +
                    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,
                    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);
After:
  aaaaaaaaaaaaaaaaa(
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177521 91177308-0d34-0410-b5e6-96231b3b80d8