MacViews: Put wm window animation calls behind an interface.

ui/views/widget/native_widget_mac.mm

Index: ui/views/widget/native_widget_mac.mm
diff --git a/ui/views/widget/native_widget_mac.mm b/ui/views/widget/native_widget_mac.mm
index b6578bc1ce63ed3f0f664c775890b4eee09955ec..be90f4a409b8a9f6b14026a9b21fa9b8493d78d8 100644
--- a/ui/views/widget/native_widget_mac.mm
+++ b/ui/views/widget/native_widget_mac.mm
@@ -82,6 +82,22 @@ gfx::Size WindowSizeForClientAreaSize(NSWindow* window, const gfx::Size& size) {
   return gfx::Size(NSWidth(frame_rect), NSHeight(frame_rect));
 }
 
+class VisibilityAnimationMac : public Widget::VisibilityAnimation {
+ public:
+  VisibilityAnimationMac() {}
+  virtual ~VisibilityAnimationMac() {}
+
+  void SetDuration(const base::TimeDelta& duration) override {
+    NOTIMPLEMENTED();
+  }
+  void SetTransition(Transition transition) override{
+    NOTIMPLEMENTED();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(VisibilityAnimationMac);
+};
+
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -90,6 +106,7 @@ gfx::Size WindowSizeForClientAreaSize(NSWindow* window, const gfx::Size& size) {
 NativeWidgetMac::NativeWidgetMac(internal::NativeWidgetDelegate* delegate)
     : delegate_(delegate),
       bridge_(new BridgedNativeWidget(this)),
+      visibility_animation_(new VisibilityAnimationMac),
       ownership_(Widget::InitParams::NATIVE_WIDGET_OWNS_WIDGET) {
 }
 
@@ -512,6 +529,10 @@ void NativeWidgetMac::SetVisibilityChangedAnimationsEnabled(bool value) {
   NOTIMPLEMENTED();
 }
 
+Widget::VisibilityAnimation* NativeWidgetMac::GetVisibilityAnimation() const {
+  return visibility_animation_.get();
+}
+
 ui::NativeTheme* NativeWidgetMac::GetNativeTheme() const {
   return ui::NativeTheme::instance();
 }