Builders must have unique names (#203)
Builders must have unique names (#203)

* Builders must have unique names

* Add TODO for updating registration code


Former-commit-id: b59178bcef88d0d4e3043f00079a8343fe0e6fab
frankbu/istio,frankbu/istio,sebastienvas/istio,sebastienvas/istio,istio/istio,sebastienvas/istio,sebastienvas/istio,mandarjog/istio,smawson/istio,frankbu/istio,istio/istio,frankbu/istio,geeknoid/istio,smawson/istio,frankbu/istio,geeknoid/istio,istio/istio,mandarjog/istio,smawson/istio,istio/istio,smawson/istio,mandarjog/istio,frankbu/istio,geeknoid/istio,mandarjog/istio,sebastienvas/istio,geeknoid/istio,geeknoid/istio,geeknoid/istio,mandarjog/istio,smawson/istio,istio/istio,smawson/istio