fix: isMultiUserSupported in TestDevice does not reflect real value

Bug: 247056506
Test: manual
Change-Id: I6f4b0c160f874d66169d7c4c6169bae7769a3e17

services/core/java/com/android/server/pm/PackageManagerShellCommand.java

@@ -314,6 +314,8 @@ class PackageManagerShellCommand extends ShellCommand {
                     return runRemoveUser();
                 case "set-user-restriction":
                     return runSetUserRestriction();
+                case "supports-multiple-users":
+                    return runSupportsMultipleUsers();
                 case "get-max-users":
                     return runGetMaxUsers();
                 case "get-max-running-users":
@@ -3014,6 +3016,12 @@ class PackageManagerShellCommand extends ShellCommand {
         return 0;
     }
 
+    public int runSupportsMultipleUsers() {
+        getOutPrintWriter().println("Is multiuser supported: "
+                + UserManager.supportsMultipleUsers());
+        return 0;
+    }
+
     public int runGetMaxUsers() {
         getOutPrintWriter().println("Maximum supported users: "
                 + UserManager.getMaxSupportedUsers());