HttpContext Items "ODataQueryOperation.Current" added twice

[mikehebert]

When querying with the "$inlinecount=allpages" option, ODataQueryProvider attempts to add the same key twice to the HttpContext.Current.Items collection.

ODataQueryProvider.cs, line 112 should be changed from:
HttpContext.Current.Items.Add("ODataQueryOperation.Current", operation);
to:
HttpContext.Current.Items["ODataQueryOperation.Current"] = operation;