XFA - Add a layer to display XFA forms (#13069)

- add an option to enable XFA rendering if any;
  - for now, let the canvas layer: it could be useful to implement XFAF forms (embedded pdf in xml stream for the background and xfa form for the foreground);
  - ui elements in template DOM are pretty close to their html counterpart so we generate a fake html DOM from template one:
    - it makes easier to translate template properties to html ones;
    - it makes faster the creation of the html element in the main thread.

src/core/pdf_manager.js

@@ -106,13 +106,14 @@ class BasePdfManager {
 }
 
 class LocalPdfManager extends BasePdfManager {
-  constructor(docId, data, password, evaluatorOptions, docBaseUrl) {
+  constructor(docId, data, password, evaluatorOptions, enableXfa, docBaseUrl) {
     super();
 
     this._docId = docId;
     this._password = password;
     this._docBaseUrl = docBaseUrl;
     this.evaluatorOptions = evaluatorOptions;
+    this.enableXfa = enableXfa;
 
     const stream = new Stream(data);
     this.pdfDocument = new PDFDocument(this, stream);
@@ -141,7 +142,14 @@ class LocalPdfManager extends BasePdfManager {
 }
 
 class NetworkPdfManager extends BasePdfManager {
-  constructor(docId, pdfNetworkStream, args, evaluatorOptions, docBaseUrl) {
+  constructor(
+    docId,
+    pdfNetworkStream,
+    args,
+    evaluatorOptions,
+    enableXfa,
+    docBaseUrl
+  ) {
     super();
 
     this._docId = docId;
@@ -149,6 +157,7 @@ class NetworkPdfManager extends BasePdfManager {
     this._docBaseUrl = docBaseUrl;
     this.msgHandler = args.msgHandler;
     this.evaluatorOptions = evaluatorOptions;
+    this.enableXfa = enableXfa;
 
     this.streamManager = new ChunkedStreamManager(pdfNetworkStream, {
       msgHandler: args.msgHandler,