Skip depth and scrim if freeform tasks are visible

If freeform tasks are shown, skip applying depth effect and scrim
changes. These cause the background to flicker while showing freeform
tasks and for example showing the transient taskbar.

Bug: 263264985
Test: swipe up to show transient taskbar, observe launcher background
does not blur or flicker to black

Change-Id: I5b10d0f0c7065e903cb761488367c02d7e31d8b2

quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java

@@ -1002,6 +1002,14 @@ public class QuickstepLauncher extends Launcher {
         mPendingSplitSelectInfo = null;
     }
 
+    @Override
+    public boolean areFreeformTasksVisible() {
+        if (mDesktopVisibilityController != null) {
+            return mDesktopVisibilityController.areFreeformTasksVisible();
+        }
+        return false;
+    }
+
     private static final class LauncherTaskViewController extends
             TaskViewTouchController<Launcher> {