Reland "[TTFPassGen] Move PasswordGenerationAgent::FocusedElementChanged call earlier"

This is a reland of commit 3c1a89031d0a3c5ef1c89a89c637ca80b1bcc629

The original CL was reverted because of the failing PasswordManagerUIUtilAndroid::ShouldNotAcceptFocusEventAfterLoosingFocus test (it's renamed to ShouldNotAcceptFocusEventAfterFrameLostFocus currently) on the android-bf-cache bot. The test was re-writted and now passes.

Original change's description:
> [TTFPassGen] Move PasswordGenerationAgent::FocusedElementChanged call earlier
>
> Now PasswordGenerationAgent::FocusedNodeHasChanged is called from AutofillAgent::DidCompleteFocusChangeInFrame, which happens later then the virtual keyboard is shown (when a text input element is navigated).
> It feels more natural to move the FocusedNodeHasChanged call to AutofillAgent::HandleFocusChangeComplete, which happens before triggering the keyboard. This is needed for the password generation bottom sheet (the bottom sheet should be able to suppress the keyboard before it's triggered).
>
> Bug: 1421753
> Change-Id: Icacfce86a448dc5ea3ab82a205bccb237328df60
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4304062
> Reviewed-by: Christoph Schwering <schwering@google.com>
> Commit-Queue: Anna Tsvirchkova <atsvirchkova@google.com>
> Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1130362}

Bug: 1421753, 1433296
Change-Id: Ief1372d9849342096370becd3bd89e8c2fe2d81e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4431191
Reviewed-by: Mohamed Amir Yosef <mamir@chromium.org>
Commit-Queue: Anna Tsvirchkova <atsvirchkova@google.com>
Reviewed-by: Christoph Schwering <schwering@google.com>
Code-Coverage: Findit <findit-for-me@appspot.gserviceaccount.com>
Reviewed-by: Ioana Pandele <ioanap@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1133719}