fix: using on events instead of addEventListener

some platforms such as WeChat, see
MirrorNetworking/Mirror#3904

source/Runtime/Client/Webgl/plugin/SimpleWeb.jslib

@@ -35,17 +35,17 @@ function Connect(addressPtr, openCallbackPtr, closeCallBackPtr, messageCallbackP
     const index = SimpleWeb.AddNextSocket(webSocket);
 
     // Connection opened
-    webSocket.addEventListener('open', function (event) {
+    webSocket.onopen = function (event) {
         console.log("Connected to " + address);
         dynCall('vi', openCallbackPtr, [index]);
-    });
-    webSocket.addEventListener('close', function (event) {
+    }
+    webSocket.onclose = function (event) {
         console.log("Disconnected from " + address);
         dynCall('vi', closeCallBackPtr, [index]);
-    });
+    }
 
     // Listen for messages
-    webSocket.addEventListener('message', function (event) {
+    webSocket.onmessage = function (event) {
         if (event.data instanceof ArrayBuffer) {
             // TODO dont alloc each time
             var array = new Uint8Array(event.data);
@@ -61,13 +61,13 @@ function Connect(addressPtr, openCallbackPtr, closeCallBackPtr, messageCallbackP
         else {
             console.error("message type not supported")
         }
-    });
+    }
 
-    webSocket.addEventListener('error', function (event) {
+    webSocket.onerror = function (event) {
         console.error('Socket Error', event);
 
         dynCall('vi', errorCallbackPtr, [index]);
-    });
+    }
 
     return index;
 }