AuthzSourcePolicy doesn't deny viewing changeset on restricted path

[Ryan J Ollos]

There seems to be an inconsistency in AuthzSourcePolicy permission checking for files and changesets. For files, a True or False decision is made based on the authz configuration: tags/trac-1.2.2/trac/versioncontrol/svn_authz.py@:219#L181​. However, for changesets the decision will be True or None: tags/trac-1.2.2/trac/versioncontrol/svn_authz.py@:223-225#L181​. When the decision is None, other policies are consulted.

Simple example:

[/dir1]
user1 = r
[/dir2]
user2 = r

Consider a change to /dir1/file1, where no users have coarse-grained FILE_VIEW and CHANGESET_VIEW. user1 can view the file and changeset and user2 cannot. Now grant FILE_VIEW and CHANGESET_VIEW to authenticated. The behavior is the same for user1. However, user2 can view the changeset but cannot view the file.

The issue may have been introduced in r10007.