Convert the only remaining consumer (in `hand_tool.js`) of the 'localized' event to use the `localized` Promise instead, and only re-dispatch the 'localized' event on the `eventBus` for `GENERIC` builds

Ideally we'd remove the 'localized' event from the `eventBus`, but for backwards compatibility we keep it in `GENERIC` builds.
Note that while we want to ensure that the direction attribute of the HTML is updated as soon as the `localized` Promise is resolved, we purposely wait until the viewer has been initialized to ensure that the 'localized' event will always be dispatched.

web/app.js

@@ -215,6 +215,14 @@ var PDFViewerApplication = {
       self.bindEvents();
       self.bindWindowEvents();
 
+      if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
+        // For backwards compatibility, we dispatch the 'localized' event on
+        // the `eventBus` once the viewer has been initialized.
+        localized.then(function () {
+          self.eventBus.dispatch('localized');
+        });
+      }
+
       if (self.isViewerEmbedded && !PDFJS.isExternalLinkTargetSet()) {
         // Prevent external links from "replacing" the viewer,
         // when it's embedded in e.g. an iframe or an object.
@@ -1788,11 +1796,6 @@ if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
   };
 }
 
-function webViewerLocalized() {
-  document.getElementsByTagName('html')[0].dir = mozL10n.getDirection();
-  PDFViewerApplication.eventBus.dispatch('localized');
-}
-
 function webViewerPresentationMode() {
   PDFViewerApplication.requestPresentationMode();
 }
@@ -2241,7 +2244,9 @@ function webViewerKeyDown(evt) {
   }
 }
 
-localized.then(webViewerLocalized);
+localized.then(function webViewerLocalized() {
+  document.getElementsByTagName('html')[0].dir = mozL10n.getDirection();
+});
 
 /* Abstract factory for the print service. */
 var PDFPrintServiceFactory = {

web/hand_tool.js

@@ -18,17 +18,19 @@
 (function (root, factory) {
   if (typeof define === 'function' && define.amd) {
     define('pdfjs-web/hand_tool', ['exports', 'pdfjs-web/grab_to_pan',
-      'pdfjs-web/preferences'], factory);
+      'pdfjs-web/preferences', 'pdfjs-web/ui_utils'], factory);
   } else if (typeof exports !== 'undefined') {
-    factory(exports, require('./grab_to_pan.js'), require('./preferences.js'));
+    factory(exports, require('./grab_to_pan.js'), require('./preferences.js'),
+      require('./ui_utils.js'));
   } else {
     factory((root.pdfjsWebHandTool = {}), root.pdfjsWebGrabToPan,
-      root.pdfjsWebPreferences);
+      root.pdfjsWebPreferences, root.pdfjsWebUIUtils);
   }
-}(this, function (exports, grabToPan, preferences) {
+}(this, function (exports, grabToPan, preferences, uiUtils) {
 
 var GrabToPan = grabToPan.GrabToPan;
 var Preferences = preferences.Preferences;
+var localized = uiUtils.localized;
 
 /**
  * @typedef {Object} HandToolOptions
@@ -59,13 +61,12 @@ var HandTool = (function HandToolClosure() {
 
     this.eventBus.on('togglehandtool', this.toggle.bind(this));
 
-    this.eventBus.on('localized', function (e) {
-      Preferences.get('enableHandToolOnLoad').then(function resolved(value) {
-        if (value) {
+    Promise.all([localized, Preferences.get('enableHandToolOnLoad')]).then(
+      function resolved(values) {
+        if (values[1] === true) {
           this.handTool.activate();
         }
-      }.bind(this), function rejected(reason) {});
-    }.bind(this));
+      }.bind(this)).catch(function rejected(reason) { });
 
     this.eventBus.on('presentationmodechanged', function (e) {
       if (e.switchInProgress) {