Use system default vibration pattern

Bug: 9468462
Change-Id: Ifa46a56873c10888da8eaa2782fe07ef138a141b
diff --git a/java/res/values/keypress-vibration-durations.xml b/java/res/values/keypress-vibration-durations.xml
index e8d9225..e2f2b56 100644
--- a/java/res/values/keypress-vibration-durations.xml
+++ b/java/res/values/keypress-vibration-durations.xml
@@ -56,7 +56,7 @@
         <item>MODEL=XT907:MANUFACTURER=motorola,30</item>
         <!-- Sony Xperia Z -->
         <item>MODEL=C6603:MANUFACTURER=Sony,35</item>
-        <!-- Default value for unknown device -->
-        <item>,20</item>
+        <!-- Default value for unknown device. The negative value means system default. -->
+        <item>,-1</item>
     </string-array>
 </resources>
diff --git a/java/res/values/strings.xml b/java/res/values/strings.xml
index 85abb08..cdc2c3a 100644
--- a/java/res/values/strings.xml
+++ b/java/res/values/strings.xml
@@ -79,6 +79,8 @@
 
     <!-- Units abbreviation for the duration (milliseconds) [CHAR LIMIT=10] -->
     <string name="abbreviation_unit_milliseconds"><xliff:g id="milliseconds">%s</xliff:g>ms</string>
+    <!-- The text that represents the current settings value is the system default [CHAR LIMIT=20] -->
+    <string name="settings_system_default">System default</string>
 
     <!-- Option name for enabling or disabling the use of names of people in Contacts for suggestion and correction [CHAR LIMIT=25] -->
     <string name="use_contacts_dict">Suggest Contact names</string>
diff --git a/java/src/com/android/inputmethod/latin/SettingsFragment.java b/java/src/com/android/inputmethod/latin/SettingsFragment.java
index 9cc1785..6587b40 100644
--- a/java/src/com/android/inputmethod/latin/SettingsFragment.java
+++ b/java/src/com/android/inputmethod/latin/SettingsFragment.java
@@ -367,6 +367,9 @@
 
             @Override
             public String getValueText(final int value) {
+                if (value < 0) {
+                    return res.getString(R.string.settings_system_default);
+                }
                 return res.getString(R.string.abbreviation_unit_milliseconds, value);
             }
         });