[Wasm64] Fix creation of 64-bit memories from JS

[sbc100]

This enables quite a few tests that were previously disabled.

The extra check for navigator.userAgent is because node added support for the navigator object: nodejs/node#47769.

This change is also part of #19959, which could land instead.

[dschuff]

This also means that once this lands, the memory64 feature will only work with Chrome builds that have the new JS API support, right?

[sbc100]

This also means that once this lands, the memory64 feature will only work with Chrome builds that have the new JS API support, right?

No.. extra attributes seem to just get ignored so it should have no effect. Even it if did it would only effect those who use IMPORTED_MEMORY (directly or indirectly).

[dschuff]

So IIUC the thing that this actually makes work is the use cases for IMPORTED_MEMORY (of which the most important is threads... and #19959 is the rest of the threads fixes).

[dschuff]

This is good to split out into a smaller change though.

[sbc100]

So IIUC the thing that this actually makes work is the use cases for IMPORTED_MEMORY (of which the most important is threads... and #19959 is the rest of the threads fixes).

Yes that sounds right. Hopefully @dakenf is OK with this change landing even though it overlaps with #19959?

[dakenf]

Sure, I'll need to update that one anyway because some tests fail