Extract some stuff into PackageManager:

- content handler determination from ApplicationManager::HandleFetchCallback
- content handler registration
- renames BaseApplicationFetcher to PackageManagerImpl.

R=yzshen@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1352663002

Cr-Commit-Position: refs/heads/master@{#349357}


CrOS-Libchrome-Original-Commit: 59e4ed2dd7f05972f687d628df0ba9c9cc35eb97
17 files changed
tree: 02156f94028e16e708d0e76e2c8c6115582d8a71
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/