SettingsActivity: Get profile parent using UserManager.getProfileParent

In the headless system user mode(hsum) non-primary users can also have a profile.
The existing implementation in SettingsActivity always gets the primary user as the profile parent, refactored the implementation to get profile parent using UserManager.getProfileParent.

Test: NA
Bug: 267162079
Change-Id: I2af581a4b7e3320f9351b862b7be3ef141b744b7
diff --git a/src/com/android/settings/SettingsActivity.java b/src/com/android/settings/SettingsActivity.java
index 143c92d..b369190 100644
--- a/src/com/android/settings/SettingsActivity.java
+++ b/src/com/android/settings/SettingsActivity.java
@@ -466,7 +466,8 @@
             if (userInfo.isManagedProfile()) {
                 trampolineIntent.setClass(this, DeepLinkHomepageActivityInternal.class)
                         .putExtra(EXTRA_USER_HANDLE, getUser());
-                startActivityAsUser(trampolineIntent, um.getPrimaryUser().getUserHandle());
+                startActivityAsUser(trampolineIntent,
+                        um.getProfileParent(userInfo.id).getUserHandle());
             } else {
                 startActivity(trampolineIntent);
             }