Don't reset the velocity when flinging down just because of falsing

The velocity was reset even if the direction was correct.

Test: collapse on the lockscreen and then fling down, observe no jitter
Bug: 32437839
Change-Id: I92454a1bb3d8156c8c3c537b266d061b16c82c7b

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

@@ -685,7 +685,7 @@ public abstract class PanelView extends FrameLayout {
         mOverExpandedBeforeFling = getOverExpansionAmount() > 0f;
         ValueAnimator animator = createHeightAnimator(target);
         if (expand) {
-            if (expandBecauseOfFalsing) {
+            if (expandBecauseOfFalsing && vel < 0) {
                 vel = 0;
             }
             mFlingAnimationUtils.apply(animator, mExpandedHeight, target, vel, getHeight());