php 5.4 notice fixes

Warning: Illegal string offset 'campaign_id' in CRM_Report_Form_Contribute_Summary->__construct() (line 227 of /home/lobo/www/drupal-7.15/sites/crm_43/modules/civicrm/CRM/Report/Form/Contribute/Summary.php).
Notice: Undefined property: CRM_Report_Form_Contribute_Summary::$_grandFlag in CRM_Report_Form->statistics() (line 2193 of/home/lobo/www/drupal-7.15/sites/crm_43/modules/civicrm/CRM/Report/Form.php).