Sending to trash should rely on content/remove policy

Currently when sending to trash only content/manage_locations policy is taken into account. To be consistent with legacy only content/remove should be verified.

Steps to reproduce:
1. Create a new user e.g. "editor".
2. Assign it to a new group e.g. editors.
3. Modify the policies for this group, so it should have content/remove but not content/manage_policies.
4. Log in as "editor" and create some content.
5. Try to remove it.
Result: in v1 there is an error: An error occurred when sending 'New article' to Trash, in v2 the "Send to trash" button is disabled.

Ref:
legacy: https://github.com/ezsystems/ezpublish-legacy/blob/master/kernel/classes/ezcontentobjecttreenode.php#L392
platform: https://github.com/ezsystems/ezpublish-kernel/blob/master/eZ/Publish/Core/Repository/TrashService.php#L120