Asynchronously get the cookie acceptance policy of this.
Note that when policy was set to webkit_cookie_policy_accept_no_third_party and ITP is enabled, this
will return webkit_cookie_policy_accept_always. See also
webkit_website_data_manager_set_itp_enabled.
When the operation is finished, callback will be called. You can then call get_accept_policy.end
to get the result of the operation.
| this | |
| cancellable |
a Cancellable or null to ignore |
| callback |
a TaskReadyCallback to call when the request is satisfied |
| user_data |
the data to pass to callback function |