Code review comment for lp:~osomon/webbrowser-app/bookmarks-proxy-model

For reference, I measured the memory overhead induced by duplicating in memory all the entries of the source model, and this is roughly 1MB per 1000 bookmarks, i.e. 1KB per bookmark (tested with 10000 bookmarks, and with 100000).

I’ll see if this can be optimized by keeping in memory only the bookmarks for the expanded folders, and reconstructing the entries for a folder when it is being expanded, and will share my observations here.