Syntax errors

• Used INHERIT_COMBINE_BY_WEIGHT instead of INHERIT_BY_WEIGHT as defined
• Do null check on $fields['type']
• Only clear cache if the node has already been saved ($node->nid is set)
• Used _inherit_get_data() instead of _inherit_get()
• Check if $parent['parent'] != 0 before retrieving field information of parent type

Patch is attached.