[test] Make msan work for v8 stand-alone.
[test] Make msan work for v8 stand-alone.

The msan configuration can be used in combination with
v8_use_snapshot=false.

BUG=chromium:425187
LOG=n

Review URL: https://codereview.chromium.org/802583003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#28064}

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh