Remove RenderFrameHost pointer from ChooserController.

chrome/browser/ui/cocoa/extensions/chooser_dialog_cocoa_controller_unittest.mm

 // Copyright 2016 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.
 
 #import "chrome/browser/ui/cocoa/extensions/chooser_dialog_cocoa_controller.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include <memory>
 #include <vector>
@@ skipping 42 matching lines @@
     CocoaProfileTest::SetUp();
     ASSERT_TRUE(browser());
   }
 
   // Create a ChooserDialogCocoa.
   void CreateChooserDialog() {
     content::WebContents* web_contents =
         content::WebContents::Create(content::WebContents::CreateParams(
             profile(), content::SiteInstance::Create(profile())));
     ASSERT_TRUE(web_contents);
-    std::unique_ptr<MockChooserController> chooser_controller(
-        new MockChooserController(web_contents->GetMainFrame()));
-    ASSERT_TRUE(chooser_controller);
+    auto chooser_controller = base::MakeUnique<MockChooserController>();
     mock_chooser_controller_ = chooser_controller.get();
     chooser_dialog_.reset(
         new ChooserDialogCocoa(web_contents, std::move(chooser_controller)));
     ASSERT_TRUE(chooser_dialog_);
     chooser_dialog_controller_ =
         chooser_dialog_->chooser_dialog_cocoa_controller_.get();
     ASSERT_TRUE(chooser_dialog_controller_);
     device_chooser_content_view_ =
         [chooser_dialog_controller_ deviceChooserContentView];
     ASSERT_TRUE(device_chooser_content_view_);
@@ skipping 1146 matching lines @@
       MockChooserController::ConnectedPairedStatus::NONE);
 
   // Select option 0 and press "Get help" button.
   [table_view_ selectRowIndexes:[NSIndexSet indexSetWithIndex:0]
            byExtendingSelection:NO];
   EXPECT_CALL(*mock_chooser_controller_, Select(testing::_)).Times(0);
   EXPECT_CALL(*mock_chooser_controller_, Cancel()).Times(0);
   EXPECT_CALL(*mock_chooser_controller_, OpenHelpCenterUrl()).Times(1);
   [help_button_ performClick:chooser_dialog_controller_];
 }