[2/n] Replace read-only desktop windowing flag with runtime flag

Replace use of `enable_desktop_windowing` flag with
`enable_desktop_windowing_mode` flag

Flag: NONE
Bug: 304778354
Fixes: 326060018
Test: build & `adb shell device_config put lse_desktop_experience
com.android.window.flags.enable_desktop_windowing_mode true && adb
reboot` desktop windowing mode should be enabled.

Change-Id: Idc44e2b7a8b738f15f8d3812a0c4fc1a4b4861c1

quickstep/src/com/android/quickstep/views/DesktopTaskView.java

@@ -52,7 +52,7 @@ import com.android.quickstep.util.RecentsOrientedState;
 import com.android.systemui.shared.recents.model.Task;
 import com.android.systemui.shared.recents.model.ThumbnailData;
 import com.android.systemui.shared.system.QuickStepContract;
-import com.android.wm.shell.Flags;
+import com.android.window.flags.Flags;
 
 import kotlin.Unit;
 
@@ -72,8 +72,6 @@ public class DesktopTaskView extends TaskView {
     private static final boolean DESKTOP_MODE_SUPPORTED = SystemProperties.getBoolean(
             "persist.wm.debug.desktop_mode_2", false);
 
-    private static final boolean ENABLE_DESKTOP_WINDOWING = Flags.enableDesktopWindowing();
-
     private static final String TAG = DesktopTaskView.class.getSimpleName();
 
     private static final boolean DEBUG = false;
@@ -97,7 +95,7 @@ public class DesktopTaskView extends TaskView {
     /** Check whether desktop windowing is enabled */
     public static boolean isDesktopModeSupported() {
         // Check for aconfig flag first
-        if (ENABLE_DESKTOP_WINDOWING) {
+        if (Flags.enableDesktopWindowingMode()) {
             return true;
         }
         // Fall back to sysprop flag