Merge lp:~abentley/launchpad/flag-enables-privacy-checks into lp:launchpad

[Aaron Bentley]

Provide disclosure.private_project.traversal_override.

= Summary =
Ensure that enabling project privacy on qastaging doesn't make it unusable for non-users.

== Proposed fix ==
Introduce disclosure.private_project.traversal_override

== Pre-implementation notes ==
Brief discussion with deryck

== LOC Rationale ==
Part of Private Projects

== Implementation details ==
Updates ViewProduct to use userCanView for anonymous users.
Adds disclosure.private_project.traversal_override flag.

== Tests ==
bin/test -t test_anonymous_traversal_override -t test_userCanView_override

== Demo and Q/A ==
- Create a proprietary product.
- Log in as an unprivileged user.
- Attempt to view the product. You should be unable to see it.
- Log out.
- Attempt to view the product. You should be unable to see it.
- Enable disclosure.private_project.traversal_override for all users.
- Log in as an unprivileged user.
- Attempt to view the product. You should be able to see it.
- Log out.
- Attempt to view the product. You should be able to see it.

= Launchpad lint =

Checking for conflicts and issues in changed files.

Linting changed files:
  lib/lp/security.py
  lib/lp/services/features/flags.py
  lib/lp/registry/model/product.py
  lib/lp/registry/tests/test_product.py

[Richard Harding (rharding)]

review: Approve