Catch nested blocks preview errors

[youknowriad]

closes #9897

This is a stopgap solution for block style variations for blocks using InnerBlocks. At the moment, rendering innerBlocks in a preview doesn't work. Details here #9897 (comment)

The solution for the root issue is a little bit complex and might require using a nested editor.

In the meantime, this is a stop-gap solution that avoid rendering the preview if it triggers an error.

Testing instructions

• Add a style variations for the columns block
• Check that you can switch style variations.

[gziolo]

Our goal is for Hooks to cover all use cases for classes as soon as possible. There are no Hook equivalents to the uncommon getSnapshotBeforeUpdate and componentDidCatch lifecycles yet, but we plan to add them soon.

😿

[gziolo]

This file contains 2 components. Wouldn't it better to handle this error in the parent BlockPreview component and don't review this part of UI at all?

Aside: it might be nice to split this into two files.

[youknowriad]

Actually, I think it's better to handle as closely as possible to the error. That way the "title" of the preview is still shown properly and just the content is left empty.

[talldan]

This seems to work fine for columns, but seeing an unusual issue when I test this on the section block. I've added the following styles (copied from the button block):

	styles: [
		{ name: 'default', label: _x( 'Default', 'block style' ), isDefault: true },
		{ name: 'outline', label: __( 'Outline' ) },
		{ name: 'squared', label: _x( 'Squared', 'block style' ) },
	],

Here's a gif:

I'm seeing the error thrown in the console, but the componentDidCatch isn't triggered.

[youknowriad]

I'm seeing the error thrown in the console, but the componentDidCatch isn't triggered.

That's fine I think. I guess this is the default behavior of componentDidCatch

This seems to work fine for columns, but seeing an unusual issue when I test this on the section

@talldan Interesting, it feels like the focus is moving somewhere we display the preview

[youknowriad]

closing in favor of #15561 which I think is a better fix.