Chromium change: https://source.chromium.org/chromium/chromium/src/+/2747c27c571886bc1a646c4ab9eb1fa46c4b29fd Use event-driven supplier for fulfillment type Replace the polling-based `isUsingAiMode()` method with an event-driven `ObservableSupplier` that reports the `NavigationFulfillmentType`. This refactoring allows consumers like the LocationBar and Autocomplete systems to react dynamically to changes in the fulfillment mode (e.g., switching between DEFAULT and AI_MODE) without needing to continuously poll for the current state. As a direct benefit, the LocationBar now observes this supplier to hide the Lens button when the fulfillment type is AI_MODE, ensuring the UI accurately reflects the available actions. Bug: 436888404 Change-Id: Iae4df3f4fc6f5d2e298765a823b3ad61aa9f1512 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6943716