[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
diff --git a/Android.bp b/Android.bp
index 4354b66..8f2e5a6 100644
--- a/Android.bp
+++ b/Android.bp
@@ -204,6 +204,7 @@
         "com_android_launcher3_flags_lib",
         "com_android_wm_shell_flags_lib",
         "android.appwidget.flags-aconfig-java",
+        "com.android.window.flags.window-aconfig-java",
     ],
     sdk_version: "current",
     min_sdk_version: min_launcher3_sdk_version,