Only free the calling_ctx after removing the data
Only free the calling_ctx after removing the data

Cleans up one possible SIGSEGV.

rickypai/zookeeper,zk-ruby/zookeeper,rickypai/zookeeper,songling88/zookeeper,songling88/zookeeper,rickypai/zookeeper,zk-ruby/zookeeper,zk-ruby/zookeeper,songling88/zookeeper,rickypai/zookeeper,songling88/zookeeper