Only fetch serial number once and improve init error messages

Test: unit tests
Bug: 175189135
Bug: 174581028
Change-Id: I64f4c1a25f48d815e7b89f08bd3069969c615d64
1 file changed
tree: edbef3377ba423b35505c6f2e9e095196a9b0fa0
  1. build/
  2. docs/
  3. emu_test/
  4. libraries/
  5. scripts/
  6. tests/
  7. utils/
  8. PREUPLOAD.cfg