Try to connect WebSocket and return error before send result to parent

When WebSocket connection error is occured, current implementation sends
result as success becuase it tries to send result before reporting
result. The error messahe also not shown because standard IOs are
closed.

Try to connect WebSocket before sending result to parent to fix this.

Author: k311093

pkg/cli/cli.go

@@ -1274,6 +1274,22 @@ func runConnectionWebSocketAgentCommand(flags *ConnectFlags, c *command, args []
 	}
 	defer tcpConn.Close()
 
+	// Connect to ADB proxy WebSocket
+	//   wss://127.0.0.1:1443/devices/cvd-1/adb
+	// Since the operator is self-signed, skip verifying cert
+	dialer := websocket.Dialer{
+		TLSClientConfig: &tls.Config{
+			InsecureSkipVerify: true,
+		},
+	}
+	device := args[0]
+	wsUrl := fmt.Sprintf("%s/devices/%s/adb", wsRoot, device)
+	wsConn, _, err := dialer.Dial(wsUrl, nil)
+	if err != nil {
+		log.Fatal("Failed to connect ", wsUrl, ": ", err)
+		return err
+	}
+
 	// Send connect result to the parent
 	result := ConnStatus{
 		ADB: ForwarderState{
@@ -1299,22 +1315,6 @@ func runConnectionWebSocketAgentCommand(flags *ConnectFlags, c *command, args []
 		cerr.Close()
 	}
 
-	// Connect to ADB proxy WebSocket
-	//   wss://127.0.0.1:1443/devices/cvd-1/adb
-	// Since the operator is self-signed, skip verifying cert
-	dialer := websocket.Dialer{
-		TLSClientConfig: &tls.Config{
-			InsecureSkipVerify: true,
-		},
-	}
-	device := args[0]
-	wsUrl := fmt.Sprintf("%s/devices/%s/adb", wsRoot, device)
-	wsConn, _, err := dialer.Dial(wsUrl, nil)
-	if err != nil {
-		log.Fatal("Failed to connect ", wsUrl, ": ", err)
-		return err
-	}
-
 	// Redirect WebSocket to ADB TCP port
 	wsWrapper := &wsIoWrapper{
 		wsConn: wsConn,