Prepare to introduce websockets for exec and portforward

Refactor the code in remotecommand to better represent the structure of
what is common between portforward and exec.

test/e2e/framework/exec_util.go

@@ -24,7 +24,6 @@ import (
 
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	remocommandconsts "k8s.io/apimachinery/pkg/util/remotecommand"
 	restclient "k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/remotecommand"
 	"k8s.io/kubernetes/pkg/api"
@@ -135,15 +134,14 @@ func (f *Framework) ExecShellInPodWithFullOutput(podName string, cmd string) (st
 }
 
 func execute(method string, url *url.URL, config *restclient.Config, stdin io.Reader, stdout, stderr io.Writer, tty bool) error {
-	exec, err := remotecommand.NewExecutor(config, method, url)
+	exec, err := remotecommand.NewSPDYExecutor(config, method, url)
 	if err != nil {
 		return err
 	}
 	return exec.Stream(remotecommand.StreamOptions{
-		SupportedProtocols: remocommandconsts.SupportedStreamingProtocols,
-		Stdin:              stdin,
-		Stdout:             stdout,
-		Stderr:             stderr,
-		Tty:                tty,
+		Stdin:  stdin,
+		Stdout: stdout,
+		Stderr: stderr,
+		Tty:    tty,
 	})
 }