We have a similar optimization for unchecked integer modulus, which
already boosted some asm.js use cases. Now this optimization is almost
as effcient as Crankshafts known power of 2 right hand side optimization
for modulus, but it can still deal with any rhs (except 0), and doesn't
require the interpreter to also collect known power of two rhs feedback.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2200453002
Cr-Commit-Position: refs/heads/master@{#38187}