This CL implements the __getLocal and __sbrk APIs of the evaluator
interface.  Also includes a drive-by fix of the imports' module: put
them on the "env" module.

Change-Id: Ie16d1b1cf924b88734eda184d1ce98d52f32f828
Bug: chromium:1020120
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2132786
Commit-Queue: Philip Pfaffe <pfaffe@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67122}