XFA - Add a parser for XFA files

- the parser is base on a class extending XMLParserBase
 - it handle xml namespaces:
   * each namespace is assocated with a builder
   * builder builds nodes belonging to the namespace
   * when a node is inserted in the parent namespace compatibility is checked (if required)
 - to avoid name collision between xml names and object properties, use Symbol.

src/core/xfa/namespaces.js

@@ -0,0 +1,81 @@
+/* Copyright 2021 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const $buildXFAObject = Symbol();
+
+const NamespaceIds = {
+  config: {
+    id: 0,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xci/"),
+  },
+  connectionSet: {
+    id: 1,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-connection-set/"),
+  },
+  datasets: {
+    id: 2,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-data/"),
+  },
+  form: {
+    id: 3,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-form/"),
+  },
+  localeSet: {
+    id: 4,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-locale-set/"),
+  },
+  pdf: {
+    id: 5,
+    check: ns => ns === "http://ns.adobe.com/xdp/pdf/",
+  },
+  signature: {
+    id: 6,
+    check: ns => ns === "http://www.w3.org/2000/09/xmldsig#",
+  },
+  sourceSet: {
+    id: 7,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-source-set/"),
+  },
+  stylesheet: {
+    id: 8,
+    check: ns => ns === "http://www.w3.org/1999/XSL/Transform",
+  },
+  template: {
+    id: 9,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xfa-template/"),
+  },
+  xdc: {
+    id: 10,
+    check: ns => ns.startsWith("http://www.xfa.org/schema/xdc/"),
+  },
+  xdp: {
+    id: 11,
+    check: ns => ns === "http://ns.adobe.com/xdp/",
+  },
+  xfdf: {
+    id: 12,
+    check: ns => ns === "http://ns.adobe.com/xfdf/",
+  },
+  xhtml: {
+    id: 13,
+    check: ns => ns === "http://www.w3.org/1999/xhtml",
+  },
+  xmpmeta: {
+    id: 14,
+    check: ns => ns === "http://ns.adobe.com/xmpmeta/",
+  },
+};
+
+export { $buildXFAObject, NamespaceIds };