Use TelephonyManager API to check if device is voice capable.

Bug: 146076829
Test: make
Change-Id: I28b708a5838054ec1baa0a086e5e2f6ccc9c0614

src/com/android/settings/CryptKeeper.java

@@ -964,7 +964,7 @@ public class CryptKeeper extends Activity implements TextView.OnEditorActionList
     }
 
     private boolean isEmergencyCallCapable() {
-        return getResources().getBoolean(com.android.internal.R.bool.config_voice_capable);
+        return getTelephonyManager().isVoiceCapable();
     }
 
     private void takeEmergencyCallAction() {