Add Flutter 3 warning workaround

@@ -187,7 +187,6 @@ class PdfXrefTable extends PdfDataType {
     }
 
     final bytes = ((math.log(offset) / math.ln2).ceil() / 8).ceil();
-    print(bytes);
     final w = [1, bytes, 1];
     params['/W'] = PdfArray.fromNum(w);
     final wl = w.reduce((a, b) => a + b);

@@ -3,6 +3,7 @@
 # 5.9.1
 
 - iOS: Set cutLength to be currentSize.height [Liam Downey]
+- Add Flutter 3 warning workaround
 
 ## 5.9.0
 

@@ -67,7 +67,9 @@ class PdfPreviewData extends ChangeNotifier {
   PdfPageFormat get actualPageFormat => _onComputeActualPageFormat();
 
   String get localPageFormat {
-    final locale = WidgetsBinding.instance!.window.locale;
+    // Flutter 3 workaround
+    final WidgetsBinding? wbi = WidgetsBinding.instance;
+    final locale = wbi!.window.locale;
     // ignore: unnecessary_cast
     final cc = (locale as Locale?)?.countryCode ?? 'US';