Fix DesktopMediaPickerViews to handle background parent_web_contents

chrome/browser/ui/views/desktop_media_picker_views_unittest.cc

 // Copyright 2014 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 "base/bind.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/media/fake_desktop_media_list.h"
 #include "chrome/browser/ui/views/desktop_media_picker_views.h"
 #include "components/web_modal/test_web_contents_modal_dialog_host.h"
@@ skipping 28 matching lines @@
     parent_widget_.reset(new Widget);
     parent_widget_->Init(params);
 
     media_list_ = new FakeDesktopMediaList();
     scoped_ptr<FakeDesktopMediaList> media_list(media_list_);
 
     base::string16 app_name = base::ASCIIToUTF16("foo");
 
     picker_views_.reset(new DesktopMediaPickerViews());
     picker_views_->Show(NULL,
+                        parent_widget_->GetNativeWindow(),
                         NULL,
-                        parent_widget_->GetNativeWindow(),
                         app_name,
                         app_name,
                         media_list.PassAs<DesktopMediaList>(),
                         base::Bind(&DesktopMediaPickerViewsTest::OnPickerDone,
                                    base::Unretained(this)));
   }
 
   virtual void TearDown() OVERRIDE {
     test_helper_->TearDown();
     ui::TerminateContextFactoryForTests();
@@ skipping 136 matching lines @@
   GetPickerDialogView()->GetMediaSourceViewForTesting(0)->OnFocus();
   EXPECT_TRUE(
       GetPickerDialogView()->IsDialogButtonEnabled(ui::DIALOG_BUTTON_OK));
 
   media_list_->RemoveSource(0);
   EXPECT_FALSE(
       GetPickerDialogView()->IsDialogButtonEnabled(ui::DIALOG_BUTTON_OK));
 }
 
 }  // namespace views