Fix TinyMCE edit link when link contains html

[satrun77]

Description

If you have a link in tinymce like <a href=""><span>Title</span></a>, then you can edit the link. The HTML inside the link tag can be any tag.

The issue is that the selected node is the inside HTML tag instead of the link tag.

I'm not 100% keen on the solution using while but this is legacy code, so might be ok! Alternative code is welcomed :)

The PR silverstripe/silverstripe-cms#2993 depends on this PR.

Manual testing steps

1. Install fresh CMS
2. Edit a page
3. Add a link (internal or external)
4. Edit HTML code in TinyMCE, add any HTML tags inside the link
5. Close the HTML code view in TInyMCE
6. Try to edit the link, it won't show the popup form.

Issues

• Cannot edit a link if markup is in the link text silverstripe-cms#2439

Pull request checklist

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• CI is green

[GuySartorelli]

The comments in silverstripe/silverstripe-cms#2993 (review) apply to this PR as well.

[satrun77]

I have updated the fix by moving the selection to the link element. This does not need the other PR. I have tested this with internal and external linking, it worked for me as expected.

[GuySartorelli]

Thanks, this works great locally. Just one tiny change to make.

[GuySartorelli]

Suggested change

	// Find "a" node, issue https://github.com/silverstripe/silverstripe-cms/issues/2439
	// Find "a" node (we might have clicked on a child element e.g. "span")

There's no need to list the issue - git blame will inevitably lead us back to this PR and then to that issue if we really need that level of context on this.

[satrun77]

Done updated

[GuySartorelli]

LGTM, works well locally. Thanks for this!