Minor adjustements on UserManager.isUserForeground().

- Uses context user id instead of calling user id.
- Annotated with @UserHandleAware.
- Updated javadoc.

Test: m update-apis
Test: atest CtsMultiUserTestCases
Bug: 173541467

Change-Id: Id61fb73f2b7313265554cff9f496eb118a7e6a1e

core/java/android/os/IUserManager.aidl

@@ -113,7 +113,7 @@ interface IUserManager {
     boolean hasBadge(int userId);
     boolean isUserUnlocked(int userId);
     boolean isUserRunning(int userId);
-    boolean isUserForeground();
+    boolean isUserForeground(int userId);
     boolean isUserNameSet(int userId);
     boolean hasRestrictedProfiles();
     boolean requestQuietModeEnabled(String callingPackage, boolean enableQuietMode, int userId, in IntentSender target, int flags);

core/java/android/os/UserManager.java

@@ -2300,13 +2300,14 @@ public class UserManager {
     }
 
     /**
-     * Checks if the calling user is running on foreground.
+     * Checks if the context user is running in the foreground.
      *
-     * @return whether the calling user is running on foreground.
+     * @return whether the context user is running in the foreground.
      */
+    @UserHandleAware
     public boolean isUserForeground() {
         try {
-            return mService.isUserForeground();
+            return mService.isUserForeground(mUserId);
         } catch (RemoteException re) {
             throw re.rethrowFromSystemServer();
         }

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

@@ -1522,11 +1522,18 @@ public class UserManagerService extends IUserManager.Stub {
     }
 
     @Override
-    public boolean isUserForeground() {
-        int callingUserId = Binder.getCallingUserHandle().getIdentifier();
+    public boolean isUserForeground(@UserIdInt int userId) {
+        final int callingUserId = UserHandle.getCallingUserId();
+        if (callingUserId != userId
+                && !hasManageUsersOrPermission(android.Manifest.permission.INTERACT_ACROSS_USERS)) {
+            throw new SecurityException("Caller from user " + callingUserId + " needs MANAGE_USERS "
+                    + "or INTERACT_ACROSS_USERS permission to check if another user (" + userId
+                    + ") is running in the foreground");
+        }
+
         int currentUser = Binder.withCleanCallingIdentity(() -> ActivityManager.getCurrentUser());
         // TODO(b/179163496): should return true for profile users of the current user as well
-        return currentUser == callingUserId;
+        return currentUser == userId;
     }
 
     @Override