Summary:
In some cases we normalize expressions to check some facts about them. In these
cases, trying to keep as much information as possible in the expression, such
as the fact it comes from a `sizeof()` expression, is not needed. Doing
destructive normalization allows us to replace `sizeof()` by its
statically-known value.
closes#706
Reviewed By: mbouaziz
Differential Revision: D5536685
fbshipit-source-id: cc3d731
Jules Villard