Give user the opportunity to chose no LED-notification.

res/values/arrays.xml

@@ -82,6 +82,7 @@
     <item>@string/preferences__cyan</item>
     <item>@string/preferences__magenta</item>
     <item>@string/preferences__white</item>
+    <item>@string/preferences__none</item>
   </string-array>
   
 
@@ -93,6 +94,7 @@
     <item>cyan</item>
     <item>magenta</item>
     <item>white</item>
+    <item>none</item>
   </string-array>
   
   <string-array name="pref_led_blink_pattern_entries">

res/values/strings.xml

@@ -693,6 +693,7 @@
     <string name="preferences__cyan">Cyan</string>
     <string name="preferences__magenta">Magenta</string>
     <string name="preferences__white">White</string>
+    <string name="preferences__none">None</string>
     <string name="preferences__fast">Fast</string>
     <string name="preferences__normal">Normal</string>
     <string name="preferences__slow">Slow</string>

src/org/thoughtcrime/securesms/notifications/MessageNotifier.java

@@ -361,12 +361,16 @@ public class MessageNotifier {
 
     builder.setSound(TextUtils.isEmpty(ringtone) || !signal ? null : Uri.parse(ringtone));
 
-    if (signal && vibrate)
+    if (signal && vibrate) {
       builder.setDefaults(Notification.DEFAULT_VIBRATE);
+    }
 
-    builder.setLights(Color.parseColor(ledColor), Integer.parseInt(blinkPatternArray[0]),
+    if (!ledColor.equals("none")) {
+      builder.setLights(Color.parseColor(ledColor),
+                        Integer.parseInt(blinkPatternArray[0]),
                         Integer.parseInt(blinkPatternArray[1]));
     }
+  }
 
   private static String[] parseBlinkPattern(String blinkPattern, String blinkPatternCustom) {
     if (blinkPattern.equals("custom"))