Avoid misleading message about NODE_ID blob
Avoid misleading message about NODE_ID blob

Summary: Currently, in the single machine execution, a misleading message is printed to the log that the 'NODE_ID' blob is not found. This diff ensures that this message is not spitting out anymore while maintaining the semantics.

Reviewed By: Maratyszcza

Differential Revision: D6302728

fbshipit-source-id: 0f45245aedf6d4f664368595f7894e0f695e5323

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