Album splitting logic doesn't seem to be correct

[seehamrun]

The ensureAlbumSize function in the PhotosContainerResource doesn't look entirely correct

https://github.com/google/data-transfer-project/blob/master/portability-types-common/src/main/java/org/datatransferproject/types/common/models/photos/PhotosContainerResource.java#L102-L139

A couple of notable things:

• The split assumes that all the images corresponding to the albums are present in the same resource
• Also assumes that the albums that images belong in are also in the same resource (which they may not be if the album was created in the prior resource).

I found this while trying to port this code to the media container resource and incorporate videos, in the meantime im going to not port this over since we have our own handling of this on the Google end and i don't think anyone else relies on this.