Fixes layouting regression and invalid-read.

Layouting would prevent breaking before + in
a[b + c] = d;
Regression detected by code review.

Also fixes an invalid-read found by the valgrind bot.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173262 91177308-0d34-0410-b5e6-96231b3b80d8