fix(Calendar Replication) add special treatment for event::exdate

Change-Id: Ia1da1094fe9f98aa189fa283133760aaa695a833
Reviewed-on: http://gerrit.tine20.com/customers/15243
Reviewed-by: Philipp Schüle <p.schuele@metaways.de>
Tested-by: Jenkins CI (http://ci.tine20.com/) <tine20-jenkins@metaways.de>

tine20/Tinebase/Record/Abstract.php

@@ -1505,7 +1505,13 @@ public function applyDiff(Tinebase_Record_Diff $diff)
                 }
             } else {
                 if (in_array($property, $this->_datetimeFields) && ! is_object($oldValue)) {
-                    $oldValue = new Tinebase_DateTime($oldValue);
+                    if (is_array($oldValue)) {
+                        foreach ($oldValue as &$tmpVal) {
+                            $tmpVal = new Tinebase_DateTime($tmpVal);
+                        }
+                    } else {
+                        $oldValue = new Tinebase_DateTime($oldValue);
+                    }
                 }
                 $this->$property = $oldValue;
             }