caffe: fix protobuf issue

[ankane]

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A change in Protobuf 3.12.3 (protocolbuffers/protobuf#7496) is causing an error when trying to build projects with Caffe.

/usr/local/opt/caffe/include/caffe/proto/caffe.pb.h:49:51: error: no type named 'AuxillaryParseTableField' in namespace 'google::protobuf::internal'; did you mean 'AuxiliaryParseTableField'?
  static const ::PROTOBUF_NAMESPACE_ID::internal::AuxillaryParseTableField aux[]
               ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
                                                  AuxiliaryParseTableField
/usr/local/include/google/protobuf/generated_message_table_driven.h:141:7: note: 'AuxiliaryParseTableField' declared here

There isn't an error when building from source, so bumping the revision should fix it (last revision was before Protobuf 3.12.3 was released).

[chenrui333]

@ankane, looks like you need a rebase. change lgtm!

[Bo98]

Is this still a problem after #58229?

[ankane]

That fixed it as well, thanks @Bo98!

[Bo98]

The changes are going to happen sometime in the future - it might be a good idea, if possible, to make the caffe test detect the breakage.

[ankane]

I'm not sure of the best way to test this one (was a dependency for another project). I imagine anytime there's a breaking change with protobuf, any formulas that generate protocol buffers will need to be updated.