Print Preview Cleanup: Creating enum with all custom events used.

chrome/browser/resources/print_preview/page_settings.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('print_preview', function() {
   'use strict';
 
   /**
    * Creates a PageSettings object. This object encapsulates all settings and
    * logic related to page selection.
@@ skipping 241 matching lines @@
     },
 
     /**
      * Executes whenever a blur event occurs on |this.selectedPagesTextfield|
      * or when the timer expires. It takes care of
      * 1) showing/hiding warnings/suggestions
      * 2) updating print button/summary
      */
     onSelectedPagesTextfieldChanged: function() {
       this.validateSelectedPages_();
-      cr.dispatchSimpleEvent(document, 'updateSummary');
-      cr.dispatchSimpleEvent(document, 'updatePrintButton');
+      cr.dispatchSimpleEvent(document, customEvents.UPDATE_SUMMARY);
+      cr.dispatchSimpleEvent(document, customEvents.UPDATE_PRINT_BUTTON);
     },
 
     /**
      * When the user stops typing in |this.selectedPagesTextfield| or clicks on
      * |allPagesRadioButton|, a new print preview is requested, only if
      * 1) The input is compeletely valid (it can be parsed in its entirety).
      * 2) The newly selected pages differ from |this.previouslySelectedPages_|.
      * @private
      */
     onSelectedPagesMayHaveChanged_: function() {
       if (this.selectedPagesRadioButton_.checked)
         this.onSelectedPagesTextfieldChanged();
 
       // Toggling between "all pages"/"some pages" radio buttons while having an
       // invalid entry in the page selection textfield still requires updating
       // the print summary and print button.
       if (!this.isPageSelectionValid() || !this.hasPageSelectionChanged_()) {
-        cr.dispatchSimpleEvent(document, 'updateSummary');
-        cr.dispatchSimpleEvent(document, 'updatePrintButton');
+        cr.dispatchSimpleEvent(document, customEvents.UPDATE_SUMMARY);
+        cr.dispatchSimpleEvent(document, customEvents.UPDATE_PRINT_BUTTON);
         return;
       }
       requestPrintPreview();
     },
 
     /**
      * Whenever |this.selectedPagesTextfield| gains focus we add a timer to
      * detect when the user stops typing in order to update the print preview.
      * @private
      */
@@ skipping 64 matching lines @@
           this.addTimerToSelectedPagesTextfield_.bind(this);
       this.selectedPagesTextfield.onblur =
           this.onSelectedPagesTextfieldBlur_.bind(this);
     }
   };
 
   return {
     PageSettings: PageSettings,
   };
 });