PDF Viewer: Forward code from key events

Currently the pdf viewer forwards the keyCode property from key events.
However, this property is deprecated, see:
https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

Add the non-deprecated code property to the list of properties to
serialize.

Note: this caused a problem with key handling in Print Preview, when
Print Preview was updated from using keyCode to code to identify the
escape key.

Bug: 890724
Change-Id: I259dd36e344f8a5095487b71df8e96d85e3af47b
Reviewed-on: https://chromium-review.googlesource.com/c/1256111Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596466}

chrome/browser/resources/pdf/pdf_scripting_api.js

@@ -12,6 +12,7 @@ function DeserializeKeyEvent(dict) {
   var e = document.createEvent('Event');
   e.initEvent('keydown', true, true);
   e.keyCode = dict.keyCode;
+  e.code = dict.code;
   e.shiftKey = dict.shiftKey;
   e.ctrlKey = dict.ctrlKey;
   e.altKey = dict.altKey;
@@ -29,6 +30,7 @@ function DeserializeKeyEvent(dict) {
 function SerializeKeyEvent(event) {
   return {
     keyCode: event.keyCode,
+    code: event.code,
     shiftKey: event.shiftKey,
     ctrlKey: event.ctrlKey,
     altKey: event.altKey,

chrome/test/data/pdf/basic_plugin_test.js

@@ -46,10 +46,12 @@ var tests = [
     viewer.isPrintPreview_ = true;
     scriptingAPI.setKeyEventCallback(chrome.test.callbackPass(function(e) {
       chrome.test.assertEq(27, e.keyCode);
+      chrome.test.assertEq('Escape', e.code);
     }));
     var e = document.createEvent('Event');
     e.initEvent('keydown');
     e.keyCode = 27;
+    e.code = 'Escape';
     document.dispatchEvent(e);
   }
 ];