Extract out the methods of Resolver::EvaluateXXXValue() to a new
tint::resolver::ConstEval class.
Removes more bloat from Resolver, and creates a centralized class for
constant evaluation, which can be referred to by the IntrinsicTable.
Change-Id: I3b58882ef293fe07f019ad2138a7e9dbbac8de53
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/95951
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>