Add rpc error for ELECTRON_BROWSER_MEMBER_GET

lib/browser/rpc-server.js

@@ -363,6 +363,11 @@ ipcMain.on('ELECTRON_BROWSER_MEMBER_SET', function (event, id, name, value) {
 ipcMain.on('ELECTRON_BROWSER_MEMBER_GET', function (event, id, name) {
   try {
     let obj = objectsRegistry.get(id)
+
+    if (obj == null) {
+      throwRPCError(`Cannot get property '${name}' on missing remote object ${id}`)
+    }
+
     event.returnValue = valueToMeta(event.sender, obj[name])
   } catch (error) {
     event.returnValue = exceptionToMeta(error)