Fixes ApnEditor not restoring previous UI

ApnEditor tries read and set the UI in onCreate, before the previous bundle
is restored. This caused problems when the configuration has changed (such
as switching to Dark Theme).

This moves the UI changes to onViewRestored

Fixes: 146399432
Test: make SettingsGoogle and manual test UI
Change-Id: I8147ec96569fa28867c088d6c36584aa344f40ed