Add a browser test that can communicate with the layout test framework and print pdfs.

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"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "chrome/browser/ui/webui/constrained_web_dialog_ui.h"
 
 class PrintPreviewDataService;
 class PrintPreviewHandler;
 struct PrintHostMsg_DidGetPreviewPageCount_Params;
 struct PrintHostMsg_RequestPrintPreview_Params;
 
 namespace base {
+class FilePath;
 class RefCountedBytes;
 }
 
 namespace gfx {
 class Rect;
 }
 
 namespace printing {
 struct PageSizeMargins;
 }
@@ skipping 116 matching lines @@
   // also instructs the dialog to auto-cancel, which is used for testing only.
   class TestingDelegate {
    public:
     virtual bool IsAutoCancelEnabled() = 0;
     virtual void DidGetPreviewPageCount(int page_count) = 0;
     virtual void DidRenderPreviewPage(content::WebContents* preview_dialog) = 0;
   };
 
   static void SetDelegateForTesting(TestingDelegate* delegate);
 
+  // Allows for tests to set a file path to print a PDF to. This also initiates
+  // the printing without having to click a button on the print preview dialog.
+  void SetSelectedFileForTesting(const base::FilePath& path);
+
  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.
   base::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_