Update some example + test code to use MdTextButton instead of

ui/views/focus/focus_manager_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 "ui/views/focus/focus_manager.h"
 
 #include <stddef.h>
 
 #include <utility>
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/base/accelerators/accelerator.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/views/accessible_pane_view.h"
-#include "ui/views/controls/button/label_button.h"
 #include "ui/views/focus/focus_manager_factory.h"
 #include "ui/views/focus/widget_focus_manager.h"
 #include "ui/views/test/focus_manager_test.h"
 #include "ui/views/test/widget_test.h"
 #include "ui/views/widget/widget.h"
 
 namespace views {
 
 enum FocusTestEventType {
   ON_FOCUS = 0,
@@ skipping 446 matching lines @@
     FocusManager* CreateFocusManager(Widget* widget,
                                      bool desktop_widget) override {
       return new FocusManagerDtorTracked(widget, dtor_tracker_);
     }
 
    private:
     DtorTrackVector* dtor_tracker_;
     DISALLOW_COPY_AND_ASSIGN(TestFocusManagerFactory);
   };
 
-  class LabelButtonDtorTracked : public LabelButton {
-   public:
-    LabelButtonDtorTracked(const base::string16& text,
-                           DtorTrackVector* dtor_tracker)
-        : LabelButton(NULL, text),
-          dtor_tracker_(dtor_tracker) {
-      SetStyle(STYLE_BUTTON);
-    };
-    ~LabelButtonDtorTracked() override {
-      dtor_tracker_->push_back("LabelButtonDtorTracked");
-    }
-
-    DtorTrackVector* dtor_tracker_;
-  };
-
   class WindowDtorTracked : public Widget {
    public:
     explicit WindowDtorTracked(DtorTrackVector* dtor_tracker)
         : dtor_tracker_(dtor_tracker) {
     }
 
     ~WindowDtorTracked() override {
       dtor_tracker_->push_back("WindowDtorTracked");
     }
 
@@ skipping 401 matching lines @@
   EXPECT_EQ(view1, GetFocusManager()->GetFocusedView());
 
   // Allow focus to go to the parent, and focus backwards which should now move
   // up |widget_view| (in the parent).
   delegate->set_should_advance_focus_to_parent(true);
   GetFocusManager()->AdvanceFocus(true);
   EXPECT_EQ(widget_view, GetFocusManager()->GetFocusedView());
 }
 
 }  // namespace views