x/build: make temporary logs redirect to permanent logs? #11141
It would be nice if people could share the live-streaming build log URLs and know that they'll always work, regardless of whether they're still live streaming or have completed (even if they're not one of the most recent 30 builds or so which we keep in memory for debugging).
If we recorded a mapping of (builder-id, rev, hexy *buildStatus pointer) => Cloud Storage URL for every build, then if the
Then we could rename the handler back to simply
FWIU, build logs are stored in Datastore by dashboard permanently, so coordinator can redirect to dashboard, and there is no need for cloud storage/bigtable (unless we want to switch from datastore to cloud storage, but that's a different issue).
Also if we store the