Add defaults for manta

Change-Id: I8784a126b02e3e6618ac845a32a894ceb58ea39e
diff --git a/java/res/values/keypress-vibration-durations.xml b/java/res/values/keypress-vibration-durations.xml
index 8f6b647..1d7e57b 100644
--- a/java/res/values/keypress-vibration-durations.xml
+++ b/java/res/values/keypress-vibration-durations.xml
@@ -23,5 +23,6 @@
         <item>herring,5</item>
         <item>tuna,5</item>
         <item>mako,20</item>
+        <item>manta,16</item>
     </string-array>
 </resources>