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

chrome/browser/ui/webui/print_preview/print_preview_ui.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_UI_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
@@ skipping 129 matching lines @@
   // Closes the print preview dialog.
   void OnClosePrintPreviewDialog();
 
   // Reload the printers list.
   void OnReloadPrintersList();
 
   // Notifies the WebUI that the pdf print scaling option is disabled by
   // default.
   void OnPrintPreviewScalingDisabled();
 
+  // Manages the global auto-cancel mode used only for testing.
+  static void SetAutoCancelForTesting(bool auto_cancel);
+  static bool AutoCancelForTesting();
+
  private:
   friend class PrintPreviewHandlerTest;
   FRIEND_TEST_ALL_PREFIXES(PrintPreviewHandlerTest, StickyMarginsCustom);
   FRIEND_TEST_ALL_PREFIXES(PrintPreviewHandlerTest, StickyMarginsDefault);
   FRIEND_TEST_ALL_PREFIXES(PrintPreviewHandlerTest,
                            StickyMarginsCustomThenDefault);
   FRIEND_TEST_ALL_PREFIXES(PrintPreviewHandlerTest,
                            GetLastUsedMarginSettingsCustom);
   FRIEND_TEST_ALL_PREFIXES(PrintPreviewHandlerTest,
                            GetLastUsedMarginSettingsDefault);
@@ skipping 25 matching lines @@
   // title.
   string16 initiator_title_;
 
   // Keeps track of whether OnClosePrintPreviewDialog() has been called or not.
   bool dialog_closed_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_UI_H_