Update documentation of FEATURE_ACTIVITIES_ON_SECONDARY_DISPLAYS

Bug: 255584489
Change-Id: I1eeaab6bc33fcc6659218c9a6555a88eb9aa7315
diff --git a/core/java/android/content/pm/PackageManager.java b/core/java/android/content/pm/PackageManager.java
index aa86af9..17c26ba 100644
--- a/core/java/android/content/pm/PackageManager.java
+++ b/core/java/android/content/pm/PackageManager.java
@@ -3817,7 +3817,10 @@
 
     /**
      * Feature for {@link #getSystemAvailableFeatures} and {@link #hasSystemFeature}:
-     * The device supports running activities on secondary displays.
+     * The device supports running activities on secondary displays. Displays here
+     * refers to both physical and virtual displays. Disabling this feature can impact
+     * support for application projection use-cases and support for virtual devices
+     * on the device.
      */
     @SdkConstant(SdkConstantType.FEATURE)
     public static final String FEATURE_ACTIVITIES_ON_SECONDARY_DISPLAYS