Reposition visible toolbar when it is in a not visible stack of rotator.

[jodator]

Suggested merge commit message (convention)

Fix: Reposition visible toolbar when it is in a not visible stack of rotator. Closes ckeditor/ckeditor5#1957.

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Additional information

• The previous fix was causing problems in some edge cases - ie when toolbar was removed on focus lost and the whole logic was re-applied twice instead of just repositioning the toolbar. See Editor crashes after moving selection outside a table while an image is selected ckeditor5#1957.

[jodator]

@Mgsy Could you test this solution? I think that this fixes the toolbar on table with image bug but it could re-introduce: https://github.com/ckeditor/ckeditor5-widget/issues/92.

cc @pjasiun & @oskarwrobel - I'm pinging you also with this as you better knew what happened in https://github.com/ckeditor/ckeditor5-widget/issues/92.

[coveralls]

Coverage remained the same at 100.0% when pulling dee7608 on t/1957 into cfd41c1 on master.

[jodator]

I didn't add any new tests as I feel that this fix looks like a better way of fixing the previous one.

Please do not merge until we decide if we're adding a test or not (I'll try to come up with a test-case anyway).

[Mgsy]

LGTM.

[jodator]

As for now I'm not able to reproduce the bug with automated test. I'll try tomorrow probably.

[Reinmar]

Heh, I know that we know this, but this API needs to be seriously rethought...

When a setter doesn't do anything, you know that it's bad.