Failing test for forwarding attributes to yielded components

[cibernox]

Extracted from emberjs/ember.js#17146

@chancancode @rwjblue I hope this reproduction helps track this down.

In the test, as it stands right now, the <Inner ...attributes> component is not rendered at all. If you remove the ...attributes it does render.

[cibernox]

ooops

[cibernox]

@chancancode did you have time to check what might be wrong with this?

[rwjblue]

I've just pushed a fix, here is the explanation from the commit message:

Prior to the changes here, for every `AttrNode` we processed we
processed its value (handling literals, mustaches, etc). The value we
process is then consumed by whatever operation is represented (e.g.
`staticArg`, `dynamicArg`, `staticAttr`, `trustingAttr`, `dynamicAttr`).
Unfortunately, when we processed the `...attributes` `AttrNode` into an
`attrSplat` we did not also ensure to consume its value (which we don't
really care about). The result was that we had one too many literal
values on the `JavascriptCompiler`'s `values` array, meaning _all_ other
operations that use a value would be getting the _prior_ operations
value (e.g. an "off by one" issue in the values array).

The fix here is to ensure that `attrSplat` consumes the value that is
pushed to ensure things stay balanced.

[cibernox]

@rwjblue great. Can we merge this? How do updates to the glimmer-vm roll out to ember versions? Could Ember 3.7.1 get this?

[rwjblue]

Will need to be backported for inclusion in Ember 3.4 LTS, 3.7, and 3.8+ into the following branches:

• release-0-35 (this is used by ember-source@3.4)
• make a release-0-36 branch (for Ember 3.7)
• make a release-0-37 (for Ember 3.8+)