Chromium change:
https://github.com/chromium/chromium/commit/e74bbb61bf7cc3c23f690fc0a93f839c8ce38f35
The new UI adds a new option to let users opt-in to extended preloading.
Also migrate where preloading prefs are controlled from
PrivacyPreferencesManager (in privacy/settings) to
chrome/browser/prefetch, which is where the UI code is also now located
(along with most features using this setting, like the prefetch proxy,
no state prefetch, omnibox search prefetching).
The migrated pref enum names have been clarified to indicate that
wifi-only preloading is deprecated. This has been unsupported for a while now,
but it was not clear from most of the call sites. Obsolete comments have
also been removed.
Bug: 1263586
samartnik
b9a839a80b