Set snackbar action color

src/main/java/org/tasks/receivers/RepeatConfirmationReceiver.java

@@ -74,6 +74,7 @@ public class RepeatConfirmationReceiver extends InjectingBroadcastReceiver {
         String snackbarText = activity.getString(R.string.repeat_snackbar, task.getTitle(), dueDateString);
 
         Snackbar.make(view, snackbarText, Snackbar.LENGTH_LONG)
+                .setActionTextColor(activity.getResources().getColor(R.color.snackbar_undo))
                 .setAction(R.string.DLG_undo, new View.OnClickListener() {
                     @Override
                     public void onClick(View v) {

src/main/res/values/colors.xml

@@ -43,5 +43,7 @@
     <color name="importance_5">#ff505050</color>
     <color name="importance_6">#ff202020</color>
 
+    <color name="snackbar_undo">#f4b400</color>
+
 </resources>