This adds variants of tests already in our test-suite that
exercise inlining fast-paths of Number.{isFinite,isInteger}.

Bug: chromium:823151, chromium:823100
Change-Id: Ibf1192b1325fb4f015acea94053fd51a7a7811a9
Reviewed-on: https://chromium-review.googlesource.com/968361Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52021}