Change animation of QSBH on keyguard expansion

Instead of translating, just animate the alpha to appear.

Test: manual in portrait handheld
Bug: 244574445
Change-Id: Ia2576ef6fc7573ac902dd2568a492bcbcbd994dc

packages/SystemUI/src/com/android/systemui/qs/QuickStatusBarHeader.java

@@ -410,9 +410,9 @@ public class QuickStatusBarHeader extends FrameLayout {
         // If forceExpanded (we are opening QS from lockscreen), the animators have been set to
         // position = 1f.
         if (forceExpanded) {
-            setTranslationY(panelTranslationY);
+            setAlpha(expansionFraction);
         } else {
-            setTranslationY(0);
+            setAlpha(1);
         }
 
         mKeyguardExpansionFraction = keyguardExpansionFraction;