Added basic browser test for window.print() from Chrome apps.

chrome/browser/resources/print_preview/native_layer.js

 // Copyright (c) 2012 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';
 
   /**
    * An interface to the native Chromium printing system layer.
    * @constructor
@@ skipping 22 matching lines @@
     global['onDidGetDefaultPageLayout'] =
         this.onDidGetDefaultPageLayout_.bind(this);
     global['onDidGetPreviewPageCount'] =
         this.onDidGetPreviewPageCount_.bind(this);
     global['reloadPreviewPages'] = this.onReloadPreviewPages_.bind(this);
     global['onDidPreviewPage'] = this.onDidPreviewPage_.bind(this);
     global['updatePrintPreview'] = this.onUpdatePrintPreview_.bind(this);
     global['printScalingDisabledForSourcePDF'] =
         this.onPrintScalingDisabledForSourcePDF_.bind(this);
     global['onDidGetAccessToken'] = this.onDidGetAccessToken_.bind(this);
+    global['autoCancelPrintPreviewForTesting'] =
+        this.autoCancelPrintPreviewForTesting_.bind(this);
   };
 
   /**
    * Event types dispatched from the Chromium native layer.
    * @enum {string}
    * @const
    */
   NativeLayer.EventType = {
     ACCESS_TOKEN_READY: 'print_preview.NativeLayer.ACCESS_TOKEN_READY',
+    AUTO_CANCEL_FOR_TESTING:
+      'print_preview.NativeLayer.AUTO_CANCEL_FOR_TESTING',
     CAPABILITIES_SET: 'print_preview.NativeLayer.CAPABILITIES_SET',
     CLOUD_PRINT_ENABLE: 'print_preview.NativeLayer.CLOUD_PRINT_ENABLE',
     DESTINATIONS_RELOAD: 'print_preview.NativeLayer.DESTINATIONS_RELOAD',
     DISABLE_SCALING: 'print_preview.NativeLayer.DISABLE_SCALING',
     FILE_SELECTION_CANCEL: 'print_preview.NativeLayer.FILE_SELECTION_CANCEL',
     FILE_SELECTION_COMPLETE:
         'print_preview.NativeLayer.FILE_SELECTION_COMPLETE',
     GET_CAPABILITIES_FAIL: 'print_preview.NativeLayer.GET_CAPABILITIES_FAIL',
     INITIAL_SETTINGS_SET: 'print_preview.NativeLayer.INITIAL_SETTINGS_SET',
     LOCAL_DESTINATIONS_SET: 'print_preview.NativeLayer.LOCAL_DESTINATIONS_SET',
@@ skipping 508 matching lines @@
     /**
      * Updates the fit to page option state based on the print scaling option of
      * source pdf. PDF's have an option to enable/disable print scaling. When we
      * find out that the print scaling option is disabled for the source pdf, we
      * uncheck the fitToPage_ to page checkbox. This function is called from C++
      * code.
      * @private
      */
     onPrintScalingDisabledForSourcePDF_: function() {
       cr.dispatchSimpleEvent(this, NativeLayer.EventType.DISABLE_SCALING);
+    },
+
+    /**
+     * Cancel the preview and close the preview dialog. This function is called
+     * from C++ testing code.
+     * @private
+     */
+    autoCancelPrintPreviewForTesting_: function() {
+      cr.dispatchSimpleEvent(
+          this, NativeLayer.EventType.AUTO_CANCEL_FOR_TESTING);
     }
   };
 
   /**
    * Initial settings retrieved from the native layer.
    * @param {boolean} isInKioskAutoPrintMode Whether the print preview should be
    *     in auto-print mode.
    * @param {string} thousandsDelimeter Character delimeter of thousands digits.
    * @param {string} decimalDelimeter Character delimeter of the decimal point.
    * @param {!print_preview.MeasurementSystem.UnitType} unitType Unit type of
@@ skipping 149 matching lines @@
       return this.serializedAppStateStr_;
     }
   };
 
   // Export
   return {
     NativeInitialSettings: NativeInitialSettings,
     NativeLayer: NativeLayer
   };
 });