Add CanMinimize to classes that implement WidgetDelegate::CanMaximize.

components/native_app_window/native_app_window_views.cc

Index: components/native_app_window/native_app_window_views.cc
diff --git a/components/native_app_window/native_app_window_views.cc b/components/native_app_window/native_app_window_views.cc
index 766b08861985b3e0f2d40f7a9f41afdc9801a11d..fb9168210365db4454b1628eaa9a1e91f67b6eab 100644
--- a/components/native_app_window/native_app_window_views.cc
+++ b/components/native_app_window/native_app_window_views.cc
@@ -218,6 +218,10 @@ bool NativeAppWindowViews::CanMaximize() const {
          !app_window_->window_type_is_panel() && !WidgetHasHitTestMask();
 }
 
+bool NativeAppWindowViews::CanMinimize() const {
+  return true;
+}
+
 base::string16 NativeAppWindowViews::GetWindowTitle() const {
   return app_window_->GetTitle();
 }