To optimize WithNeed, which is called for the local device whenever an index
update is received. No tracking for remote devices to conserve db space, as
WithNeed is only queried for completion.
I'm trying to slowly clean this up a bit, and moving functionality out
into the folder types and having those methods not reach into model is
part of it. That can mean takign some odd arguments in the meantime,
some of those should probably become interfaces or properties on folder
in the long term.
The functionality was anyway mostly implemented there and not isolated
in the folderScanner type. The attempt to refactor it out in the other
direction wouldn't work given that the event loop and stuff is on
`folder`.
This adds a couple of utilities for transporting databases in JSON and a
test to load a database and verify a couple of invalid bits. The test
itself is quite pointless at the moment, but it lays the groundwork for
testing the migration of this data in the next step (after the invalid
bit should be changed to local flags for local files).
When that happens we need to have a database in the old format already
there in order to be able to test the migration.
The directive lives in its own isolated scope (where we put the visible() function). The stuff transcluded into the notification directive lives in the root scope and doesn't have access to the directive scope. Hence we cannot call dismiss() from inside the directive.
Similarly, config does not exist by itself in the directive scope, we need $parent to access the root scope.
Reference: https://docs.angularjs.org/guide/directive#isolating-the-scope-of-a-directive
How this worked before is a mystery. My guess is Angular bug with directive scope that was fixed in 1.3. One possibility is that transclude plus scope: true (which doesn't make sense as that is supposed to be an object) resulted in the root scope being used in the directive itself. This would then "work" as long as there is only one notification, as visible() and dismiss() would then be registered on the root scope, thus accessible from within the notification but also overridden by any notification rendered.
