Refactor sending notification from HistoryBackend
Introduce an interface HistoryBackendNotifier that forward
HistoryBackend notifications to the intended recipients.
Change AndroidProviderBackend to use HistoryBackendNotifier
instead of HistoryBackend::Delegate (this will be required
once NOTIFICATION_HISTORY_URLS_{DELETED,MODIFIED} have been
converted to observers instead).
Change ExpireHistoryBackend to use HistoryBackendNotifier
instead of ExpireHistoryBackendDelegate since the new class
interface is a superset of the class.
BUG=373326
Review URL: https://codereview.chromium.org/
708653003
Cr-Commit-Position: refs/heads/master@{#303815}