Cleanup: Remove unneeded chrome/common/pref_names.h includes.

chrome/browser/ui/webui/print_preview/print_preview_ui_unittest.cc

 // 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.
 
 #include <vector>
 
 #include "base/memory/ref_counted_memory.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/printing/print_preview_dialog_controller.h"
 #include "chrome/browser/printing/print_preview_test.h"
 #include "chrome/browser/printing/print_view_manager.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/browser/ui/webui/print_preview/print_preview_ui.h"
-#include "chrome/common/pref_names.h"
 #include "chrome/test/base/browser_with_test_window_test.h"
 #include "components/web_modal/web_contents_modal_dialog_manager.h"
 #include "content/public/browser/plugin_service.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/browser/web_contents.h"
 #include "printing/print_job_constants.h"
 
 using content::WebContents;
 using web_modal::WebContentsModalDialogManager;
 
@@ skipping 197 matching lines @@
   cancel = false;
   preview_ui->GetCurrentPrintPreviewStatus(preview_ui_addr, kFirstRequestId,
                                            &cancel);
   EXPECT_TRUE(cancel);
 
   cancel = true;
   preview_ui->GetCurrentPrintPreviewStatus(preview_ui_addr, kSecondRequestId,
                                            &cancel);
   EXPECT_FALSE(cancel);
 }