When voicemail number is unknown, show voicemail setup on notification click.

1. In NotificationMgr changed intent when no voicemail number is found so
that it will trigger opening of the voicemail screen.
2. In CallFeaturesSetting added new intent extra to indicate we just want
to open the voicemail settings.  This intent is used by Google Voice, and
I wanted to ensure that the code path for that case is not changed, hence
the new extra.

Bug: 17795834
Change-Id: I62b3d6c99558dc698565459aa0d43cd4efdd6fdd
diff --git a/src/com/android/phone/SubscriptionInfoHelper.java b/src/com/android/phone/SubscriptionInfoHelper.java
index 347d00e..f325b1a 100644
--- a/src/com/android/phone/SubscriptionInfoHelper.java
+++ b/src/com/android/phone/SubscriptionInfoHelper.java
@@ -36,10 +36,10 @@
  * helping extract this info and perform common operations using this info.
  */
 public class SubscriptionInfoHelper {
-    private static final int NO_SUB_ID = -1;
+    public static final int NO_SUB_ID = -1;
 
     // Extra on intent containing the id of a subscription.
-    private static final String SUB_ID_EXTRA =
+    public static final String SUB_ID_EXTRA =
             "com.android.phone.settings.SubscriptionInfoHelper.SubscriptionId";
     // Extra on intent containing the label of a subscription.
     private static final String SUB_LABEL_EXTRA =