the new sync framework

[Casey Link]

> UnionJob: as the result of this job both collections contain the union
> of the tracks in both collections, i.e. it adds tracks that are in
> collection A but not in collection B to B and tracks that are in B but
> not in A to A. It does not remove tracks from either A or B.
>
> OneWaySynchronizationJob: it ensures that all tracks that are in the
> source collection are present in the target collection as well, i.e.
> it adds tracks that are in source but not in target to target. It does
> not remove any tracks from target. It is one half of UnionJob.
>
> MasterSlaveSynchronizationJob: ensures that the slave collection
> contains exactly the same tracks as the master collection, i.e. it
> adds tracks that are in master but not in slave to slave and removes
> tracks that are in slave but not in master from slave.
>
>
> You might want to add this as comments to the header files.
Done.

I understand the way the sync jobs are supposed to work, however there
is a missing bit.. check out the use cases below.

Use Case 1:
User wants their ipod to have all their local tracks
Solution:  Use Master/Slave syncjob with local=master and ipod=slave. Done.

Use Case 2:
User wants to sync only a subset of their local tracks to their ipod.
Solution: ?

How (and where) should this filtering been done. Perhaps a generic
ProxyCollection should be created (similar to a proxymodel) that could
be passed a Collection and a filter, then pass the ProxyCollection to
the Master/Slave sync job.

Casey