Import FileAPI tests from web-platform-tests

LayoutTests/imported/web-platform-tests/FileAPI/idlharness.worker.js

+importScripts("/resources/testharness.js");
+importScripts("/resources/WebIDLParser.js", "/resources/idlharness.js");
+
+var request = new XMLHttpRequest();
+request.open("GET", "idlharness.idl");
+request.send();
+request.onload = function() {
+    var idl_array = new IdlArray();
+    var idls = request.responseText;
+
+    idl_array.add_untested_idls("[Global] interface Window { };");
+
+    idl_array.add_untested_idls("interface ArrayBuffer {};");
+    idl_array.add_untested_idls("interface ArrayBufferView {};");
+    idl_array.add_untested_idls("interface URL {};");
+    idl_array.add_untested_idls("interface EventTarget {};");
+    idl_array.add_untested_idls("interface Event {};");
+    idl_array.add_untested_idls("[TreatNonCallableAsNull] callback EventHandlerNonNull = any (Event event);");
+    idl_array.add_untested_idls("typedef EventHandlerNonNull? EventHandler;");
+
+
+    var worker_idls =
+            '[Constructor, Exposed=Worker]\n' +
+            'interface FileReaderSync {\n' +
+            '\n' +
+            '  // Synchronously return strings\n' +
+            '\n' +
+            '  ArrayBuffer readAsArrayBuffer(Blob blob);\n' +
+            '  DOMString readAsText(Blob blob, optional DOMString label);\n' +
+            '  DOMString readAsDataURL(Blob blob);\n' +
+            '};';
+
+    idl_array.add_idls(idls);
+    idl_array.add_idls(worker_idls);
+
+    idl_array.add_objects({
+        Blob: ['new Blob(["TEST"])'],
+        File: ['new File(["myFileBits"], "myFileName")'],
+        FileReader: ['new FileReader()'],
+        FileReaderSync: ['new FileReaderSync()']
+    });
+
+    idl_array.test();
+    done();
+};