[WebKit] Image2 throws IndexSizeError while undoing deletion of partially uploaded image

[kkrzton]

Steps to reproduce

1. Go to ​http://tests.ckeditor.dev:1030/tests/plugins/uploadwidget/manual/image2.
2. Drop image into editor.
3. Select the image with some surrounding text.
4. Delete selection while the image is still being uploaded.
5. Click undo.

Expected result

Deleted text should be brought back (without image) by undo.

Actual result

Deleted text is brought back (without image) by undo and error is thrown (in Chrome: Uncaught IndexSizeError: Failed to execute 'setEnd' on 'Range': There is no child at offset 11.; in Opera: Uncaught IndexSizeError: Failed to execute 'setEnd' on 'Range': The offset 7 is larger than or equal to the node's length (5).)

Other details (browser, OS, CKEditor version, installed plugins)