Add a "Simplify Page" option to the print preview dialog

chrome/browser/resources/print_preview/data/ticket_items/print_friendly.js

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2015 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.ticket_items', function() {
   'use strict';
 
   /**
    * Ticket item whose value is a {@code boolean} that represents whether to
-   * print selection only.
+   * simplify the page before printing.
    * @param {!print_preview.DocumentInfo} documentInfo Information about the
    *     document to print.
+   * @param {!print_preview.SelectionOnly} selectionOnly Ticket definig whether
+   *     only selected content should be printed.
    * @constructor
    * @extends {print_preview.ticket_items.TicketItem}
    */
-  function SelectionOnly(documentInfo) {
+  function PrintFriendly(documentInfo, selectionOnly) {
     print_preview.ticket_items.TicketItem.call(
         this,
         null /*appState*/,
         null /*field*/,
         null /*destinationStore*/,
         documentInfo);
+
+    this.isAvailable_ = false;
+
+    this.selectionOnly_ = selectionOnly;
   };
 
-  SelectionOnly.prototype = {
+  PrintFriendly.prototype = {
     __proto__: print_preview.ticket_items.TicketItem.prototype,
 
     /** @override */
     wouldValueBeValid: function(value) {
       return true;
     },
 
     /** @override */
     isCapabilityAvailable: function() {
-      return this.getDocumentInfoInternal().isModifiable &&
-             this.getDocumentInfoInternal().hasSelection;
+      return this.isAvailable_ && !this.selectionOnly_.isCapabilityAvailable();

[Aleksey Shlyapnikov, 2015/07/07 01:26:17]

Wouldn't the behavior be pretty random for the unsuspecting user? Any text
selected on the page will cause this option to disappear, even if user wants to
print the entire page and unaware of the selection.

     },
 
     /** @override */
     getDefaultValueInternal: function() {
       return false;
     },
 
     /** @override */
     getCapabilityNotAvailableValueInternal: function() {
       return false;
+    },
+
+    setIsCapabilityAvailable: function(isAvailable) {
+      this.isAvailable_ = isAvailable;
+      this.dispatchChangeEventInternal();

[Aleksey Shlyapnikov, 2015/07/07 01:26:17]

Dispatch this event only when the value was actually changed.

     }
   };
 
   // Export
   return {
-    SelectionOnly: SelectionOnly
+    PrintFriendly: PrintFriendly
   };
 });