[Patch] ErrorOr is not a pointer, don't use a pointer API.

[Rafael Espíndola]

> This sounds good.

Thanks. r198792, r198797 and r198799.

This will do for now. I guess I should just put these uses of * and ->
along << in my list of strange c++ patterns :-)

In my mind ErrorOr is semantically closer to a boost::variant<T,
error_code>, but we would need at least convenience methods like getAs
and castAs to make it easier to use.

Cheers,
Rafael