Merge "Add virtual display support for multi window mode" into main

core/java/android/companion/virtual/flags/flags.aconfig

@@ -52,4 +52,15 @@ flag {
     description: "Makes MediaDrm APIs device-aware"
     bug: "303535376"
     is_fixed_read_only: true
-}
\ No newline at end of file
+}
+
+flag {
+    namespace: "virtual_devices"
+    name: "virtual_display_multi_window_mode_support"
+    description: "Add support for WINDOWING_MODE_MULTI_WINDOW to virtual displays by default"
+    is_fixed_read_only: true
+    bug: "341151395"
+    metadata {
+        purpose: PURPOSE_BUGFIX
+    }
+}

core/java/android/window/DisplayWindowPolicyController.java

@@ -23,6 +23,7 @@ import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.UserIdInt;
 import android.app.WindowConfiguration;
+import android.companion.virtualdevice.flags.Flags;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.content.pm.ActivityInfo;
@@ -66,6 +67,9 @@ public abstract class DisplayWindowPolicyController {
     public DisplayWindowPolicyController() {
         synchronized (mSupportedWindowingModes) {
             mSupportedWindowingModes.add(WindowConfiguration.WINDOWING_MODE_FULLSCREEN);
+            if (Flags.virtualDisplayMultiWindowModeSupport()) {
+                mSupportedWindowingModes.add(WindowConfiguration.WINDOWING_MODE_MULTI_WINDOW);
+            }
         }
     }