Fix split-shade expansion animation on non-lockscreen.

Before this change, the notifications side was showing much earlier than
the qs side of the shade. The motion spec is for both to show up at the same time.

This is a partial revert of ag/18566290

Test: NotificationPanelViewControllerTest.java
Test: NotificationStackScrollLayoutTest.java
Test: Manually
Bug: 214946307
Change-Id: I013ba4e793c7b5f6c3ec6991b33700e58ee839b5

packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationStackScrollLayout.java

@@ -1371,12 +1371,7 @@ public class NotificationStackScrollLayout extends ViewGroup implements Dumpable
      */
     @ShadeViewRefactor(RefactorComponent.COORDINATOR)
     public void setExpandedHeight(float height) {
-        final float shadeBottom = getHeight() - getEmptyBottomMargin();
         final boolean skipHeightUpdate = shouldSkipHeightUpdate();
-        if (!skipHeightUpdate) {
-            final float expansionFraction = MathUtils.saturate(height / shadeBottom);
-            mAmbientState.setExpansionFraction(expansionFraction);
-        }
         updateStackPosition();
 
         if (!skipHeightUpdate) {

packages/SystemUI/src/com/android/systemui/statusbar/phone/PanelViewController.java

@@ -808,6 +808,7 @@ public abstract class PanelViewController {
             mExpansionDragDownAmountPx = h;
             mExpandedFraction = Math.min(1f,
                     maxPanelHeight == 0 ? 0 : mExpandedHeight / maxPanelHeight);
+            mAmbientState.setExpansionFraction(mExpandedFraction);
             onHeightUpdated(mExpandedHeight);
             updatePanelExpansionAndVisibility();
         });