Update preference screen title.

- Add missing title to preference screen xml so that they will be used to
set the activity title when the fragment is launched.
- Also updated some incorrect preference screen titles.
- Overrides getTitle() in preference fragments that do not use the
preference screen xml.

Bug: 64564191
Test: blaze-bin/screenshots/android/i18nscreenshots/i18nscreenshots
Change-Id: Id72d5ddf18f0962bc484de8bbd847a2e55d6371e

src/com/android/settings/UserCredentialsSettings.java

@@ -18,6 +18,7 @@ package com.android.settings;
 
 import android.annotation.LayoutRes;
 import android.annotation.Nullable;
+import android.annotation.StringRes;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.app.DialogFragment;
@@ -84,6 +85,12 @@ public class UserCredentialsSettings extends SettingsPreferenceFragment
         }
     }
 
+    @Override
+    @StringRes
+    protected int getTitle() {
+        return R.string.user_credentials;
+    }
+
     protected void announceRemoval(String alias) {
         if (!isAdded()) {
             return;