default user agent strings

tools/conf/transport_authenticators.go

@@ -49,6 +49,13 @@ func (this *HTTPAuthenticatorRequest) Build() (*http.RequestConfig, error) {
 				Name:  "Host",
 				Value: []string{"www.baidu.com", "www.bing.com"},
 			},
+			{
+				Name: "User-Agent",
+				Value: []string{
+					"Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36",
+					"Mozilla/5.0 (iPhone; CPU iPhone OS 10_0_2 like Mac OS X) AppleWebKit/601.1 (KHTML, like Gecko) CriOS/53.0.2785.109 Mobile/14A456 Safari/601.1.46",
+				},
+			},
 		},
 	}