Revert "[Settings] Convert to getSystemService(Class<T>)"

Revert submission 1645152-getSystemService(Class<T>)

Reason for revert: Fix JUnit test failure
Reverted Changes:
I1b4812044:[Settings] Convert to getSystemService(Class<T>)
I278951c24:[Settings] Support getSystemService(Class<T>)

Change-Id: I864a40f82ba9cb4170900ac0c1d77f781b17341f

src/com/android/settings/wifi/dpp/WifiDppUtils.java

@@ -403,8 +403,8 @@ public class WifiDppUtils {
      *                        device security or if lock screen is unlocked
      */
     public static void showLockScreen(Context context, Runnable successRunnable) {
-        final KeyguardManager keyguardManager = context.getSystemService(
-                KeyguardManager.class);
+        final KeyguardManager keyguardManager = (KeyguardManager) context.getSystemService(
+                Context.KEYGUARD_SERVICE);
 
         if (keyguardManager.isKeyguardSecure()) {
             final BiometricPrompt.AuthenticationCallback authenticationCallback =