This adds the `$request` parameter to the `permissions_check()` methods within `WP_REST_Widgets_Controller` and adds `$request` as an allowed parameter to the `permissions_check()` method within `WP_REST_Templates_Controller`.
Even when this parameter is not used by default, it should be implemented to support the class being extended and the method overidden.
Props johnbillion, timothyblynjacobs.
Fixes#53593.
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git-svn-id: http://core.svn.wordpress.org/trunk@50958 1a063a9b-81f0-0310-95a4-ce76da25c4cd