PHP notices when attempting to delete/trash/untrash a deleted post

[johnbillion]

If you attempt to delete, trash or untrash a post that has been deleted prior, WP will die with wp_die() but you'll get some notices too.

[johnbillion]

Patch.

[johnbillion]

Example notice FYI:
Notice: Trying to get property of non-object in wp-admin\post.php on line 246
This refers to the $post_type_object variable which isn't an object when the post doesn't exist.

[ocean90]

There is already a $post_type_object check for the edit action, see trunk/wp-admin/post.php:23929#L142​, which we could use here too.

Related: #20064

[SergeyBiryukov]

In 24201:

Avoid PHP notices when deleting or restoring an item that no longer exists. props johnbillion, ocean90. fixes #24246.