elasticsearch/elasticsearch — pull request #5800 by s1monw (2014-04-14 15:32:41+00:00)
Title: Ensure close is called under lock in the case of an engine failure

Until today we did close the engine without aqcuireing the write lock
since most calls were still holding a read lock. This commit removes
the code that holds on to the readlock when failing the engine which
means we can simply call #close()