Ok, I think I found a bug in the way we unregister pending heuristic providers that causes us to always wait for the whole 200ms timer when the result doesn't return any result. In addition, we should probably not wait for the omnibox provider because we have no control over its performance characteristics.
Bug 1842381 Comment 2 Edit History
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Ok, I think I found a bug in the way we unregister pending heuristic providers that causes us to always wait for the whole 200ms timer when the provider doesn't return any result. In addition, we should probably not wait for the omnibox provider because we have no control over its performance characteristics.