rand dart fix

deprecated/flutter_multi_window/lib/src/new_window/web.dart

@@ -10,17 +10,9 @@ void newWindow(
 }) {
   final screen = html.window.screen;
   double top = 0;
-  if (dy != null) {
-    top = dy;
-  } else if (screen.height != null) {
-    top = (screen.height - height) / 2;
-  }
+  top = dy;
   double left = 0;
-  if (dx != null) {
-    left = dx;
-  } else if (screen.width != null) {
-    left = (screen.width - width) / 2;
-  }
+  left = dx;
   final sb = StringBuffer();
   sb.write("height=");
   sb.write(height);

deprecated/flutter_multi_window/lib/src/window.dart

@@ -64,8 +64,6 @@ class NewWindow {
   }
 
   static NewWindow fromMap(Map<String, dynamic> map) {
-    if (map == null) return null;
-
     return NewWindow(
       url: map['url'],
       width: map['width'],
@@ -114,8 +112,8 @@ void createWindow(NewWindow window) {
     window.url,
     window.width,
     window.height,
-    dx: window?.offsetX,
-    dy: window?.offsetY,
-    name: window?.name,
+    dx: window.offsetX,
+    dy: window.offsetY,
+    name: window.name,
   );
 }

deprecated/flutter_multi_window/main.dart

@@ -84,10 +84,10 @@ class _MyAppState extends State<MyApp> {
     final height = size.height;
     final width = size.width;
     final sb = StringBuffer();
-    final top = offset?.dy ??
+    final top = offset.dy ??
         (screen.height != null ? (screen.height - height) / 2 : 0);
     final left =
-        offset?.dx ?? (screen.width != null ? (screen.width - width) / 2 : 0);
+        offset.dx ?? (screen.width != null ? (screen.width - width) / 2 : 0);
     sb.write("height=");
     sb.write(height);
     sb.write(",width=");