Add <selectedcontent> element

[josepharhar]

The <selectedoption> element is part of the customizable select feature and is being added to HTML here.

It is already implemented in chromium and will be shipped when customizable <select> is shipped.

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labels: needs implementation commitment, needs changelog entry

Closes #0000

test case

• TODO HTML validator
• TODO IBM equal access accessibility checker
• TODO axe-core
• TODO ARC toolkit

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Preview | Diff

[scottaohara]

would generally agree with this... just again noting to make sure this is thought about regarding how this gets mapped in html aam and if that could result in anything useful being allowed here.

[scottaohara]

Noting here that there will need to be an entry for a button as a child of a select as well.

[josepharhar]

Noting here that there will need to be an entry for a button as a child of a select as well.

Where should I put this?

[scottaohara]

Noting here that there will need to be an entry for a button as a child of a select as well.

Where should I put this?

oh no worries @josepharhar that was a note for me, not so much for you.

if you did want to take it on, we'd need a new button as a child of a select entry in the table - using a similar ID like I'm setting up over in html aam el-button-select-child

but really, don't worry about it. i was planning on working on finishing this PR once the HTML/HTML AAM PRs were a bit closer to done.