Set default wp_global_styles

[spacedmonkey]

Trac ticket:

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[github-actions]

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[swissspidy]

For reference, the issue now is this PHP warning when accessing the REST API:

<b>Warning</b>:  Undefined property: Gutenberg_REST_Global_Styles_Revisions_Controller_6_5::$parent_post_type

[github-actions]

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[getdave]

Gutenberg_REST_Global_Styles_Revisions_Controller_6_5

I believe possibly because the extended class sets that property access to private

wordpress-develop/src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php

Line 25 in e9ab1c1

private $parent_post_type;

Exploring also in WordPress/gutenberg#58972

[jonnynews]

This fixes the e2e tests - 95db1e9

[getdave]

Testing with Gutenberg Plugin active as per original bug report I could not reproduce the original error with these changes in this PR.

Reverting those changes manually sees the error re-appear.

I also ended up coming up with much the same fix on Gutenberg repo so I'm fairly confident this is good.

[spacedmonkey]

Now that global controller changes have been reverted, we need a new patch that reapply them. To that end, here is the original PR with a fix applied. Closing this PR in favour of this #6105