ims-ext: Restore getLteDataUsage method for backward compatibility

Removed in commit c6c474c4ee331a1c0eb1b54f7f9d515a7a7af21e,
but still needed for old prebuilt apks.

Change-Id: I1f55d247a07b65d2a7b45b88887bf05185a02a2e
diff --git a/ims/ims-ext-common/src/org/codeaurora/ims/QtiVideoCallDataUsage.java b/ims/ims-ext-common/src/org/codeaurora/ims/QtiVideoCallDataUsage.java
index 70054c1..5756ea3 100644
--- a/ims/ims-ext-common/src/org/codeaurora/ims/QtiVideoCallDataUsage.java
+++ b/ims/ims-ext-common/src/org/codeaurora/ims/QtiVideoCallDataUsage.java
@@ -92,6 +92,13 @@
     }
 
     /*
+     * This method returns LTE Data Usage (for backward compatibility)
+     */
+    public long getLteDataUsage() {
+        return getWwanDataUsage();
+    }
+
+    /*
      * This method returns WWAN Data Usage
      */
     public long getWwanDataUsage() {