Brakes or bearing?

Put the beryl on the road this week after half year on the sidelines. Started driving & before too long had a vibration on the front right while braking. The vibration is rotational and only while braking. The brakes are new all around. I adjusted one of the pads (spring had gotten out of position) but the vibration persisted. Replaced the pads with a spare set, same problem, vibration right front while braking. Interestingly there's no vibration the first time or two I stop from cold, but the more I drive the more the vibration appears.

I'm now suspecting wheel bearing. Not sure what else it could be. Am I on the right path? Seems odd that a wheel bearing problem would only happen while braking; driving (non-braking) is fine. Any thoughts?