Pass cmd flags of GlobalInit down to workers in Flow
Pass cmd flags of GlobalInit down to workers in Flow

Summary:
It's a similar trick to dyndeps. The idea is that global state is better to be just replicated to gang workers as otherwise it causes a lot of confusion.

In particular it's useful if one wants to enable detailed logging (--v)

For other operators user still needs to call GlobalInit explicitly. We should consider doing it for all Flow operators, but I'll leave it for future considerations.

Reviewed By: kennyhorror

Differential Revision: D4460686

fbshipit-source-id: 5836737dd3195f9ad12589fd899a3ff63f173e05

caffe2/caffe2,davinwang/caffe2,sf-wind/caffe2,sf-wind/caffe2,xzturn/caffe2,bwasti/caffe2,davinwang/caffe2,bwasti/caffe2,pietern/caffe2,xzturn/caffe2,bwasti/caffe2,xzturn/caffe2,bwasti/caffe2,xzturn/caffe2,xzturn/caffe2,Yangqing/caffe2,sf-wind/caffe2,davinwang/caffe2,sf-wind/caffe2,pietern/caffe2,Yangqing/caffe2,pietern/caffe2,pietern/caffe2,Yangqing/caffe2,bwasti/caffe2,Yangqing/caffe2,Yangqing/caffe2,davinwang/caffe2,pietern/caffe2,sf-wind/caffe2,davinwang/caffe2