This change completes support for import assertions for dynamic import().

A new version of the HostImportModuleDynamically callback taking import
assertions is added to the public API. The name is very verbose; we
could consider removing the "ImportAssertions" part when the old API
is removed.

Bytecode generation is updated to pass the assertions, if present, to
Runtime_DynamicImportCall.

Isolate::RunHostImportModuleDynamicallyCallback extracts the assertions
from the options bag, filters out the assertions not present in the
list specified by the host in HostGetSupportedImportAssertions, and
sorts them by code point order of the keys per
https://tc39.es/proposal-import-assertions/#sec-import-call-runtime-semantics-evaluation.
The resulting array is passed to the host in the callback.

Bug: v8:10958
Change-Id: I931df00f954a9f9c65bff5bcf461ba1c8f11e94e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2620578
Commit-Queue: Dan Clark <daniec@microsoft.com>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72307}

1) Computed property keys (esp functions in them) shouldn't be inside
the object literal scope.

2) I was using an imprecise "maybe uses super" and storing it to
preparse data. This won't fly, since it pollutes sister scopes and
leads to confusion wrt whether an object literal needs a home object
or not. Made it precise (mostly cancelling changes in the original CL).

3) PreParser::NewSuperPropertyReference was creating a VariableProxy for
this_function (which made it used) -> inconsistent scopes between
parsing and preparsing.

4) MultipleEntryBlockContextScope was messing up the accumulator

Original: https://chromium-review.googlesource.com/c/v8/v8/+/2563275

This saves memory (the home object doesn't need to be stored for each
method, but only once per class) and hopefully makes the home object
a constant in the optimized code.

Detailed documentation of the changes:
https://docs.google.com/document/d/1ZVXcoQdf9IdMsnRI9iyUjyq9NDoEyx9nA3XqMgwflMs/edit?usp=sharing

Bug: v8:9237, chromium:1167918, chromium:1167981, chromium:1167988, chromium:1168055
Change-Id: I4f53f18cc18762c33e53d8c802909b42f1c33538
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2637220Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72169}