Print Preview: Show error message if text is typed in Copies section

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

 // Copyright (c) 2016 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';
 
   /**
    * Scaling ticket item whose value is a {@code string} that indicates what the
    * scaling (in percent) of the document should be. The ticket item is backed
@@ skipping 27 matching lines @@
    * @private {number}
    * @const
    */
   Scaling.MIN_VAL = 10;
 
   Scaling.prototype = {
     __proto__: print_preview.ticket_items.TicketItem.prototype,
 
     /** @override */
     wouldValueBeValid: function(value) {
-      if (/[^\d]+/.test(value)) {
-        return false;
-      }
-      var scaling = parseInt(value, 10);
-      return scaling >= Scaling.MIN_VAL && scaling <= Scaling.MAX_VAL;
-    },
+      return true;

[dpapad, 2017/02/27 21:56:02]

Is this resulting in the same behavior as before?

[rbpotter, 2017/02/28 00:12:59]

It should be. This function was only called in isValid and in
scaling_settings. isValid was never called. scaling_settings now
checks validity.valid on the input.
This is different from copies because scaling is not allowed to update
to an invalid value since that would change the preview. Copies can
update to an invalid value, so isValid gets checked before the print
ticket gets sent for an actual print/before the print button is
enabled.

+   },
 
     /** @override */
     isValueEqual: function(value) {
       return this.getValueAsNumber() == value;
     },
 
-    /**
-     * @param {number} The desired scaling percentage.
-     * @return {number} Nearest valid scaling percentage
-     */
-    getNearestValidValue: function(value) {
-      return Math.min(Math.max(value, Scaling.MIN_VAL), Scaling.MAX_VAL);
-    },
-
     /** @override */
     isCapabilityAvailable: function() {
       // This is not a function of the printer, but should be disabled if we are
       // saving a PDF to a PDF.
       var knownSizeToSaveAsPdf =
           (!this.getDocumentInfoInternal().isModifiable ||
            this.getDocumentInfoInternal().hasCssMediaStyles) &&
            this.getSelectedDestInternal() &&
            this.getSelectedDestInternal().id ==
                print_preview.Destination.GooglePromotedId.SAVE_AS_PDF;
@@ skipping 14 matching lines @@
     getCapabilityNotAvailableValueInternal: function() {
       return '100';
     },
   };
 
   // Export
   return {
     Scaling: Scaling
   };
 });