We have some flaky integration tests elsewhere that have no one place
to ask about the state of the world. This makes LocalBackend be that
place (as it's basically there anyway) but doesn't yet add the ForTest
accessor method.
This adds a LocalBackend.peers map[NodeID]NodeView that is
incrementally updated as mutations arrive. And then we start moving
away from using NetMap.Peers at runtime (UpdateStatus no longer uses
it now). And remove another copy of NodeView in the LocalBackend
nodeByAddr map. Change that to point into b.peers instead.
Future changes will then start streaming whole-node-granularity peer
change updates to WatchIPNBus clients, tracking statefully per client
what each has seen. This will get the GUI clients from receiving less
of a JSON storm of updates all the time.
Updates #1909
Change-Id: I14a976ca9f493bdf02ba7e6e05217363dcf422e5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
9538e9f970