Sloppy eval extends the outer declaration scope's context. This is also
true for sloppy eval inside of other sloppy evals -- the outer declaration
scope's context is extended rather than the outer sloppy eval's
declaration scope. However, we consider eval scopes to also be declaration
scopes, for the purposes of strict eval and caching lookup variables. So,
we need to make sure that we skip through sloppy eval scopes when marking
a scope as calls_sloppy_eval.

In fact, we implement this rather as never marking sloppy eval scopes as
calls_sloppy_eval, under the assumption that the parent scope will already
have been marked calls_sloppy_eval by the outer eval.

As a drive-by, fix a TODO to move this logic from calls_sloppy_eval() to
RecordEvalCall(), rename the variable to something more meaningful, and
make Snapshotting to use a new calls_eval bit on Scope.

Bug: chromium:996751
Change-Id: I27ccc7ef429a7ce60b3bb02bf64a3820ae4a2c36
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1773247
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63455}