[Android][3PPWM] Ignore IsEnabled and load config timely for CCTs

CCTs create webContents in a way that doesn't allow reading the pref
before the autofill machinery is initialized. With this CL, the pref
value is passed in on creation which fixes the issue.

Another, less frequent issue is checking isEnabled. This method lazily
initializes Android's AutofillManager and contributes to CCTs
occasionally preventing Autofill use. This is incorrect since the return
value may change while the app is running and isn't suitable for making
an initial decision about whether Autofill should be enabled. The
safeguard this provided is (already or by now) checked in the Android
Framework when the regular notifyViewEntered calls are invoked.

Just out of caution and because this fix affects a fully launched
feature, both changes are guarded with a new feature:
kAutofillVirtualViewStructureAndroidInCct.

Unlaunching the original feature isn't a good option but holding this
fix back is a bad option, too. Therefore, it's default-enabled and
intended to use only as a possible kill-switch.

The change shouldn't affect WebView but we'll add a flag as guard.

go/scrcast/NTMyNTYxNTEwMzIxMzU2OHw1OTZhYTJlZC02Yg

DD: go/3ppwm-dd
Fixed: 411164104
Change-Id: Iaf8ac48eef3fbf833d49d67c3e427d8c8d4d53b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6491087
Reviewed-by: Jan Keitel <jkeitel@google.com>
Reviewed-by: Calder Kitagawa <ckitagawa@chromium.org>
Reviewed-by: Nasko Oskov <nasko@chromium.org>
Commit-Queue: Friedrich Hauser <friedrichh@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1453749}