Add EditableText scroll into view breaking change note

[tgucio]

Breaking change note for flutter/flutter#109114

Presubmit checklist

• This PR doesn’t contain automatically generated corrections (Grammarly or similar).
• This PR follows the Google Developer Documentation Style Guidelines — for example, it doesn’t use i.e. or e.g., and it avoids I and we (first person).
• This PR uses semantic line breaks of 80 characters or fewer.

[sfshaza2]

A few tweaks and a question.

[sfshaza2]

Not sure what you mean by "on updates".

Suggested change

	To date, `EditableText` has used multiple mechanisms ensuring the selection
	extent or caret is scrolled into view on updates.
	Previously, `EditableText` used multiple mechanisms to determine the
	extent of the selection, or to ensure that the caret is scrolled into view.

[tgucio]

Thanks for the edits. Yes, this is a bit convoluted: what I meant were the mechanisms used on scrolling into view (which happens on user updates) to determine either of:

• selection extent (non-collapsed selection)
• caret position (collapsed selection).

Let me reword as:

Previously, upon scrolling into view to show user updates, EditableText used multiple mechanisms to determine the extent of the selection or the caret location.

[sfshaza2]

What does "use the most up to selection extent location" mean?
I've made some tweaks, but would do more once I understand this phrase.

Suggested change

	By removing the `Editable.onCaretChanged` callback, `EditableText` will always
	use the most up to selection extent location when scrolling to show it.
	Specifically this results in improved scroll into view behavior after
	changing selection from collapsed to non-collapsed via
	`userUpdateTextEditingValue()`.
	By removing the `Editable.onCaretChanged` callback, `EditableText` will always
	use the most up to selection extent location when scrolling to show it.
	Specifically, this improves scroll into view behavior after
	changing selection from collapsed to non-collapsed using
	`userUpdateTextEditingValue()`.

[tgucio]

The underlying issue had to do with using multiple sources of truth where one wasn't necessarily up to date (could be one frame behind).

What is clearly missing is "date" as in "up to date" :). Correcting this.

[sfshaza2]

The 3.13 release? It's probably best to just say "TBD" for now.

[tgucio]

@sfshaza2 wondering if you could take another look so we can merge framework's PR 109114? Thanks!

[sfshaza2]

lgtm. Thanks, @tgucio!