Remove some more LabelButton::STYLE_BUTTON references.

ash/shell/widgets.cc

Index: ash/shell/widgets.cc
diff --git a/ash/shell/widgets.cc b/ash/shell/widgets.cc
index c94b0cb8fc758a86ec318dce7745abd4cf684a0e..42e7f629235012b795b2ecf55f0f2a9a8e209c86 100644
--- a/ash/shell/widgets.cc
+++ b/ash/shell/widgets.cc
@@ -8,7 +8,7 @@
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/gfx/canvas.h"
 #include "ui/views/controls/button/checkbox.h"
-#include "ui/views/controls/button/label_button.h"
+#include "ui/views/controls/button/md_text_button.h"
 #include "ui/views/controls/button/radio_button.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
@@ -53,9 +53,12 @@ class WidgetsWindow : public views::WidgetDelegateView {
 };
 
 WidgetsWindow::WidgetsWindow()
-    : button_(new views::LabelButton(NULL, base::ASCIIToUTF16("Button"))),
-      disabled_button_(
-          new views::LabelButton(NULL, base::ASCIIToUTF16("Disabled button"))),
+    : button_(
+          views::MdTextButton::CreateMdButton(nullptr,
+                                              base::ASCIIToUTF16("Button"))),
+      disabled_button_(views::MdTextButton::CreateMdButton(
+          nullptr,
+          base::ASCIIToUTF16("Disabled button"))),
       checkbox_(new views::Checkbox(base::ASCIIToUTF16("Checkbox"))),
       checkbox_disabled_(
           new views::Checkbox(base::ASCIIToUTF16("Checkbox disabled"))),
@@ -74,10 +77,8 @@ WidgetsWindow::WidgetsWindow()
       radio_button_selected_disabled_(new views::RadioButton(
           base::ASCIIToUTF16("Radio button selected disabled"),
           1)) {
-  button_->SetStyle(views::Button::STYLE_BUTTON);
   AddChildView(button_);
   disabled_button_->SetEnabled(false);
-  disabled_button_->SetStyle(views::Button::STYLE_BUTTON);
   AddChildView(disabled_button_);
   AddChildView(checkbox_);
   checkbox_disabled_->SetEnabled(false);