Fix content editable not autohiding saved state notification

Make sure the correct trigger_source is passed for content editables instead of always passing AutofillSuggestionTriggerSource::kContentEditableClicked. This allows the AutoFillPopupController to set a close timer for kComposeDialogLostFocus trigger_sources.

Bug: 331964491, b/331497693
Change-Id: Ie3b984e4eb192f8bb0980325c4ea6cf6421eac77
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5406364


Reviewed-by: Trevor Perrier <perrier@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: edchin <edchin@google.com>
Cr-Commit-Position: refs/heads/main@{#1280326}