[VOL-4291] Rw-core updates for gRPC migration

Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/golang/mock/gomock/callset.go b/vendor/github.com/golang/mock/gomock/callset.go
index e4e85d6..49dba78 100644
--- a/vendor/github.com/golang/mock/gomock/callset.go
+++ b/vendor/github.com/golang/mock/gomock/callset.go
@@ -16,6 +16,7 @@
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 )
 
@@ -95,7 +96,7 @@
 		_, _ = fmt.Fprintf(&callsErrors, "there are no expected calls of the method %q for that receiver", method)
 	}
 
-	return nil, fmt.Errorf(callsErrors.String())
+	return nil, errors.New(callsErrors.String())
 }
 
 // Failures returns the calls that are not satisfied.