Media File link configuration option does not work for external images

[tharglet]

Describe the bug
When I add a external image in an image block, the "Media File" button does not work when trying to make it into a link

To reproduce
Steps to reproduce the behavior:

1. Create a new post in Wordpress 5.4
2. Insert an image block
3. Click "Insert from URL"
4. Insert a valid URL for an image (e.g. one on Imgur)
5. Click the "Insert link" button
6. Click "Media File"

Expected behavior
The image becomes a link to the media file inserted in step 4. Instead, nothing happens

Desktop (please complete the following information):

• OS: Windwos 10
• Browser Chrome
• Version 80.0.3987.163

Additional context

• Please add the version of Gutenberg you are using in the description.
  Unsure of how to find this. Using WP5.4 with no editor plugins.

Images inserted from upload or the galleryDescribe the bug
When I add a external image in an image block, the "Media File" button does not work when trying to make it into a link

To reproduce
Steps to reproduce the behavior:

1. Create a new post in Wordpress 5.4
2. Insert an image block
3. Click "Insert from URL"
4. Insert a valid URL for an image (e.g. one on Imgur)
5. Click the "Insert link" button
6. Click "Media File"

Expected behavior
The image becomes a link to the media file inserted in step 4. Instead, nothing happens

Desktop (please complete the following information):

• OS: Windwos 10
• Browser Chrome
• Version 80.0.3987.163

Additional context

• Please add the version of Gutenberg you are using in the description.
  Unsure of how to find this. Using WP5.4 with no editor plugins.

The Media File button works correctly with images inserted from the gallery or as an upload.

[johngodley]

Confirmed that trying to set the link on an externally hosted image to either 'media page' or 'attachment page' doesn't set the link or close the popup. Tested in master.

The problem seems to be caused by this code:

https://github.com/WordPress/gutenberg/blob/master/packages/block-library/src/image/edit.js#L376

The URL for externally hosted images is stored in url, not href.

Additionally I don't think it makes sense to have the attachment page as an option.

[kirilzh]

I see that this bug only exists when adding an image from URL. Uploading a local file works as expected.

Edit: The problem is that props.image in packages/block-library/src/image/edit.js is null.