Add confirm dialog test

This test will dismiss a confirm dialog box.

Author: ankur22

tests/frame_test.go

@@ -33,6 +33,9 @@ func TestFrameDismissDialogBox(t *testing.T) {
 		{
 			name: "alert",
 		},
+		{
+			name: "confirm",
+		},
 	}
 
 	for _, tt := range tests {

tests/static/dialog.html

@@ -9,6 +9,8 @@
                 case "alert":
                     alert("Click accept");
                     break;
+                case "confirm":
+                    confirm("Click accept")
             }
         </script>
     </head>