The implementation in Parser doesn't descend into sub-thread.
Re-use the getThreadSummary method in ThreadItem and traverse
the thread properly.
Bug: T298617
Change-Id: I318d9012eb83f37ccbe463923524ef2e9f995ced
We can no longer change IDs so easily, because they're stored in the
permalink database, so remove this mechanism to make sure it's not
accidentally used in the future.
Change-Id: I392ee1f49c48fc2f23d05e9a37c643438b4f2b9a
Rename ThreadItem to ContentThreadItem, then create a new ThreadItem
interface containing only the methods that we'll be able to implement
using only the persistently stored data (no parsing), then create a
DatabaseThreadItem. Do the same for CommentItem and HeadingItem.
ThreadItemSet gets a similar treatment, but it's basically only for
Phan's type checking. (This is sad.)
Change-Id: I1633049befe8ec169753b82eb876459af1f63fe8