clear_all() clears all (non-send data)

[Trashtalk217]

Objective

Since #20934, World::clear_all and World::clear_all_entities behave identically. World::clear_all used to clear all resources and entities, but since resources are now components, World::clear_all_entities also does this.

Solution

Since World::clear_all_non_send() was not included in World::clear_all, I've decided to include it.

[alice-i-cecile]

Is there any reason why this is in draft?

[Trashtalk217]

The draft was a mistake. I'm not sure why this was marked 'M-migration-guide', I've added a small note at the bottom of the resources-as-components migration guide.

I also think this is no longer blocked, since we no longer plan to revert #20934.

[alice-i-cecile]

I'm not sure why this was marked 'M-migration-guide', I've added a small note at the bottom of the resources-as-components migration guide.

This label should persist even after the migration guide is easier, to help people looking to bisect breaking changes :)

Sounds good to me otherwise; I'm fine to merge this in.