Move navigation bar logic to its own class

Start hacking away at PhoneStatusBar by trying to pull out
as much NavigationBar logic as possible.

Test: runtest systemui
Change-Id: I23b904428be31b91f0747fd60c9f6e0dd323eb44
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java
index 82a5cc2..d48819a 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java
@@ -289,7 +289,7 @@
             lp.width = panelWidth;
             lp.gravity = panelGravity;
             mQsFrame.setLayoutParams(lp);
-            mQs.getView().post(mUpdateHeader);
+            post(mUpdateHeader);
         }
 
         lp = (FrameLayout.LayoutParams) mNotificationStackScroller.getLayoutParams();