Wrapped cleanup of page and destory of document in try/finally blocks

@@ -290,7 +290,7 @@ class PrintingPlugin extends PrintingPlatform {
     await _initPlugin();
 
     final t = PdfJs.getDocument(Settings()..data = document);
-
+    try {
       final d = await promiseToFuture<PdfJsDoc>(t.promise);
       final numPages = d.numPages;
 
@@ -298,10 +298,12 @@ class PrintingPlugin extends PrintingPlatform {
           js.context['document'].createElement('canvas');
 
       final context = canvas.getContext('2d') as html.CanvasRenderingContext2D?;
-    final _pages = pages ?? Iterable<int>.generate(numPages, (index) => index);
+      final _pages =
+          pages ?? Iterable<int>.generate(numPages, (index) => index);
 
       for (final i in _pages) {
         final page = await promiseToFuture<PdfJsPage>(d.getPage(i + 1));
+        try {
           final viewport =
               page.getViewport(Settings()..scale = dpi / PdfPageFormat.inch);
 
@@ -333,10 +335,14 @@ class PrintingPlugin extends PrintingPlatform {
             canvas.height!,
             data.toBytes(),
           );
+        } finally {
           page.cleanup();
         }
+      }
+    } finally {
       t.destroy();
     }
+  }
 }
 
 class _WebPdfRaster extends PdfRaster {