[MacPorts] #57117: upgrade last users of protobuf-cpp to protobuf3-cpp

[MacPorts]

#57117: upgrade last users of protobuf-cpp to protobuf3-cpp
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  Reporter:  pmetzger           |      Owner:  (none)
      Type:  enhancement        |     Status:  new
  Priority:  Normal             |  Milestone:
 Component:  ports              |    Version:
Resolution:                     |   Keywords:
      Port:  shogun-devel sumo  |
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Comment (by kencu):

 was caffe actually fixed? I think we just default now to a compiler that
 defaults to c++11 --- which is where we started with this plan!

 Sometimes, that truly is the simplest fix, if not pure.

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Ticket URL: <https://trac.macports.org/ticket/57117#comment:18>
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