It was a bit too aggressive.

With this patch, we keep on breaking here:
  aaaaaaaaaaaaa(aaaaaaa,
                "aaaaaaa"
                "bbbbbbb");

But don't break in:
  aaaaaaaaaaaaa(aaaaaaa, aaaaaaaa("aaaaaaa"
                                  "bbbbbbb"));

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240024 91177308-0d34-0410-b5e6-96231b3b80d8