_CPThemeAttribute fix : encode missing _defaultTheme value

AppKit/CPTheme.j

@@ -579,6 +579,7 @@ CPThemeStateCircular        = CPThemeState("circular");
         _cache = {};
 
         _name = [aCoder decodeObjectForKey:@"name"];
+        _defaultValue = [aCoder decodeObjectForKey:@"defaultValue"];
         _values = [CPDictionary dictionary];
 
         if ([aCoder containsValueForKey:@"value"])
@@ -611,6 +612,7 @@ CPThemeStateCircular        = CPThemeState("circular");
 - (void)encodeWithCoder:(CPCoder)aCoder
 {
     [aCoder encodeObject:_name forKey:@"name"];
+    [aCoder encodeObject:_defaultValue forKey:@"defaultValue"];
 
     var keys = [_values allKeys],
         count = keys.length;