Improve documentation for NetworkCallbacks.

Bug: 139570489
Test: m doc-comment-check-docs
Change-Id: I9e13057b7e46908863156986429ff2ce93d4be78
1 file changed
tree: f8858400e24e62f024fc08e3bb9b019eacad4b56
  1. core/
  2. services/
  3. tests/