Add wrapper method to GsmAlphabet for API compatibility.

An internal method was changed to add parameters to support a new
feature (7-bit national language tables). Add a compatibility
wrapper for the original method signature, which is used by OEM code.

Bug: 5334032
Change-Id: I1acba369b1c1da52c4a950fd4ae21d693652e9c5

Author: Jake Hamby

telephony/java/com/android/internal/telephony/GsmAlphabet.java

@@ -204,6 +204,24 @@ private GsmAlphabet() { }
         }
     }
 
+    /**
+     * Converts a String into a byte array containing the 7-bit packed
+     * GSM Alphabet representation of the string. If a header is provided,
+     * this is included in the returned byte array and padded to a septet
+     * boundary. This method is used by OEM code.
+     *
+     * @param data The text string to encode.
+     * @param header Optional header (including length byte) that precedes
+     * the encoded data, padded to septet boundary.
+     * @return Byte array containing header and encoded data.
+     * @throws EncodeException if String is too large to encode
+     * @see #stringToGsm7BitPackedWithHeader(String, byte[], int, int)
+     */
+    public static byte[] stringToGsm7BitPackedWithHeader(String data, byte[] header)
+            throws EncodeException {
+        return stringToGsm7BitPackedWithHeader(data, header, 0, 0);
+    }
+
     /**
      * Converts a String into a byte array containing the 7-bit packed
      * GSM Alphabet representation of the string. If a header is provided,