Changing "DoubleDigitGreaterThan", which was consuming the result of a
multiplication, to "ProductGreaterThan", which performs both steps.

Bug: v8:6791
Change-Id: I7dbad350ff9b8228e11682d9691a1574ea5b0b58
Reviewed-on: https://chromium-review.googlesource.com/683614Reviewed-by: Daniel Ehrenberg <littledan@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48243}