elasticsearch/elasticsearch — pull request #6044 by kimchy (2014-05-05 10:13:29+00:00)
Title: Remove operation threading from broadcast actions

Similar to search removal, the operation threading options are not really ued, and the default should always be used. This also considerably simplifies the code.
A side affect is that we can now remove the ShardIterator#firstOrNull method, which can cause for sneaky bugs to occur.