CMS 5: Cannot delete image in WYSIWYG with delete button

[GuySartorelli]

#1312 results in some regressions which we've decided to handle as separate issues. This is one of those.

In CMS 4 it was possible to simply select (by clicking on) an image in the WYSIWYG and then press the "delete" button on the keyboard to delete it. That isn't working in CMS 5.

Turns out that's not true - that only happens in CMS 4 if you double click on the item. That still works in CMS 5.
But to ease the flow, we should add a "delete" button to the toolbar that appears when you click on an image.

Acceptance criteria

• When you click on an image to select it, the toolbar that appears includes a delete button which deletes the image

Stretch goal

• Images can be deleted by moving the text cursor to be before them and the pressing the "delete" key
• Images can be deleted by moving the text cursor to be after them and the pressing the "backspace" key
• Images can be deleted by selecting them and then pressing the "delete" key

PRs

• ENH Add delete buttons for images/embeds in wysiwyg silverstripe-asset-admin#1331

[GuySartorelli]

PR was merged