Cleanup definition of ActivityState and ApplicationStatus warnings

Removed the redundant ActivityStateEnum intdef definition and resolved
lint warnings in the ActivityState and ApplicationStatus classes.

Also updated the c++ enum conversion doc about the new IntDef
declaration style that was added in
https://crrev.com/14f477472e0e8612c98763b68e9a51bcae954c24

BUG=707186

Review-Url: https://codereview.chromium.org/2877743002
Cr-Commit-Position: refs/heads/master@{#471432}


CrOS-Libchrome-Original-Commit: 2b5c5e827022eb7f91ae9036181151576c0ade65
2 files changed
tree: a5a6585ea0455fe413a361289b1f32adde132b29
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/