[Central Surfaces] Make NotificationPanelView a singleton.

Bug: 277762009
Test: compiles; shade works
Change-Id: I69cadfeb95892105784fcf4718a3ba9b5e13298f

packages/SystemUI/src/com/android/systemui/shade/NotificationShadeWindowView.java

@@ -84,10 +84,6 @@ public class NotificationShadeWindowView extends FrameLayout {
         setMotionEventSplittingEnabled(false);
     }
 
-    public NotificationPanelView getNotificationPanelView() {
-        return findViewById(R.id.notification_panel);
-    }
-
     @Override
     public WindowInsets onApplyWindowInsets(WindowInsets windowInsets) {
         final Insets insets = windowInsets.getInsetsIgnoringVisibility(systemBars());

packages/SystemUI/src/com/android/systemui/shade/ShadeModule.kt

@@ -50,5 +50,14 @@ abstract class ShadeModule {
         ): NotificationStackScrollLayout {
             return notificationShadeWindowView.findViewById(R.id.notification_stack_scroller)
         }
+
+        // TODO(b/277762009): Only allow this view's controller to inject the view. See above.
+        @Provides
+        @SysUISingleton
+        fun providesNotificationPanelView(
+            notificationShadeWindowView: NotificationShadeWindowView,
+        ): NotificationPanelView {
+            return notificationShadeWindowView.findViewById(R.id.notification_panel)
+        }
     }
 }

packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java

@@ -134,14 +134,6 @@ public abstract class StatusBarViewModule {
         }
     }
 
-    /** */
-    @Provides
-    @CentralSurfacesComponent.CentralSurfacesScope
-    public static NotificationPanelView getNotificationPanelView(
-            NotificationShadeWindowView notificationShadeWindowView) {
-        return notificationShadeWindowView.getNotificationPanelView();
-    }
-
     /** */
     @Binds
     @CentralSurfacesComponent.CentralSurfacesScope