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
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 43772e4..03ddd6a 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -3317,4 +3317,12 @@
             return false; // Return false to continue iterating through all the items.
         });
     }
+
+    /**
+     * Returns {@code true} if there are visible tasks with windowing mode set to
+     * {@link android.app.WindowConfiguration#WINDOWING_MODE_FREEFORM}
+     */
+    public boolean areFreeformTasksVisible() {
+        return false; // Base launcher does not track freeform tasks
+    }
 }