[networking] add socket count metrics and reports

The idea here is that we'll be able to see movement in the total number
of sockets across the fleet in addition to churn, which should help us
identify resource leaks.

Change-Id: Ib823baadb63f5244c6fc95b5e6dc6119f195a6fd
2 files changed
tree: 0b4845681253436e06e5c0d49decd9c78116248f
  1. .gitignore
  2. BUILD.gn
  4. check.py
  5. cobalt_internal/
  6. fuchsia/
  7. projects.yaml