Fix flickering when long swiping from an app

Since we update the progress of the launcher anim when
recents scrolls, we were essentially jumping back to
the overview state every couple frames. Now we don't
update that shift once we're in long swipe mode.

Bug: 111926330
Change-Id: Ib751becb70df71679ff7557f113d6339a39777d0

quickstep/src/com/android/quickstep/WindowTransformSwipeHandler.java

@@ -422,7 +422,9 @@ public class WindowTransformSwipeHandler<T extends BaseDraggingActivity> {
             mSyncTransactionApplier = applier;
         });
         mRecentsView.setOnScrollChangeListener((v, scrollX, scrollY, oldScrollX, oldScrollY) -> {
-            updateFinalShift();
+            if (!mBgLongSwipeMode) {
+                updateFinalShift();
+            }
         });
         mRecentsView.setRecentsAnimationWrapper(mRecentsAnimationWrapper);
         mRecentsView.setClipAnimationHelper(mClipAnimationHelper);