Fix a bug that would lead to bad line break decisions in for loops.

Before:
    for (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa = aaaaaaaaaaaaaaa
             .aaaaaaaaaaaaaaaa;
         aaaaaaaaaaa != aaaaaaaaaaaaaaaaaaa; ++aaaaaaaaaaa) {}

After:
    for (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa =
             aaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaa;
         aaaaaaaaaaa != aaaaaaaaaaaaaaaaaaa; ++aaaaaaaaaaa) {}

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173695 91177308-0d34-0410-b5e6-96231b3b80d8
FileCheck'ize test


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173696 91177308-0d34-0410-b5e6-96231b3b80d8
FileCheck'ize and merge tests


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173697 91177308-0d34-0410-b5e6-96231b3b80d8