Fix NPE in onCreate

Use TextUtils.equals for null-safe string comparison

Bug:18337966
Change-Id: I19b39c43636e04fcefabccdfff097bb3383f088f
diff --git a/src/com/android/phone/CallFeaturesSetting.java b/src/com/android/phone/CallFeaturesSetting.java
index 4651677..2755bd7 100644
--- a/src/com/android/phone/CallFeaturesSetting.java
+++ b/src/com/android/phone/CallFeaturesSetting.java
@@ -1129,7 +1129,7 @@
         // Show the voicemail preference in onResume if the calling intent specifies the
         // ACTION_ADD_VOICEMAIL action.
         mShowVoicemailPreference = (icicle == null) &&
-                getIntent().getAction().equals(ACTION_ADD_VOICEMAIL);
+                TextUtils.equals(getIntent().getAction(), ACTION_ADD_VOICEMAIL);
 
         mSubscriptionInfoHelper = new SubscriptionInfoHelper(getIntent());
         mSubscriptionInfoHelper.setActionBarTitle(