Bug 836790 - pre: add Logger.startLoggingToConsole().
Bug 836790 - pre: don't run session.advance in separate thread in EnsureClusterURLStage.
Bug 836790 - pre: remove unused generality in RepositorySession.getBundle.
Bug 836790 - pre: always fetch and check info/counts in SafeConstrainedServer11Repository.shouldSkip().

This means that every sync we fetch info/counts and check for
validity.  Users with more than 5000 bookmarks on the server will stop
syncing entirely.
Bug 836790 - Act on RepositorySession.dataAvailable.

This commit moves the dataAvailable call into RecordsChannel and uses
it to possibly short circuit fetchSince.
Bug 836790 - Test RepositorySession.shouldSkip.
Bug 836790 - Implement Server11Repository.dataAvailable.

This couples InfoCollections and Server11Repository.  It is possible
to do this kind of test above the server sync stage level, but the
existing architecture is in place to do it closer to the repository
session level, so let's do it.
Bug 836790 - Add getter for RepositorySession.lastSyncTimestamp.

This will allow us to delegate the getter in MiddlewareRepositorySession.
Bug 836790 - Make MiddlewareRepositorySession.{shouldSkip,dataAvailable,unbundle,getLastSyncTimestamp} delegate to inner repository.