VOL-2112 move to voltha-lib-go

Change-Id: Ic1af08003c1d2c698c0cce371e64f47b47b8d875
diff --git a/vendor/google.golang.org/grpc/picker_wrapper.go b/vendor/google.golang.org/grpc/picker_wrapper.go
index a2575c9..45baa2a 100644
--- a/vendor/google.golang.org/grpc/picker_wrapper.go
+++ b/vendor/google.golang.org/grpc/picker_wrapper.go
@@ -120,6 +120,14 @@
 			bp.mu.Unlock()
 			select {
 			case <-ctx.Done():
+				if connectionErr := bp.connectionError(); connectionErr != nil {
+					switch ctx.Err() {
+					case context.DeadlineExceeded:
+						return nil, nil, status.Errorf(codes.DeadlineExceeded, "latest connection error: %v", connectionErr)
+					case context.Canceled:
+						return nil, nil, status.Errorf(codes.Canceled, "latest connection error: %v", connectionErr)
+					}
+				}
 				return nil, nil, ctx.Err()
 			case <-ch:
 			}
@@ -165,6 +173,11 @@
 			}
 			return t, done, nil
 		}
+		if done != nil {
+			// Calling done with nil error, no bytes sent and no bytes received.
+			// DoneInfo with default value works.
+			done(balancer.DoneInfo{})
+		}
 		grpclog.Infof("blockingPicker: the picked transport is not ready, loop back to repick")
 		// If ok == false, ac.state is not READY.
 		// A valid picker always returns READY subConn. This means the state of ac