fix(wire-protocol): 2.6 killCursor should not way for reply

NODE-1088

Author: mbroadst

lib/connection/pool.js

@@ -287,7 +287,6 @@ function connectionFailureHandler(self, event) {
     // Flush all work Items on this connection
     while (this.workItems.length > 0) {
       var workItem = this.workItems.shift();
-      // if(workItem.cb) workItem.cb(err);
       if (workItem.cb) workItem.cb(err);
     }
 

lib/wireprotocol/2_6_support.js

@@ -106,8 +106,6 @@ WireProtocol.prototype.killCursor = function(bson, ns, cursorState, pool, callba
     } catch (err) {
       callback(err, null);
     }
-
-    return;
   }
 
   // Callback

test/tests/unit/single/sessions_tests.js

@@ -217,7 +217,7 @@ describe('Sessions (Single)', function() {
     }
   });
 
-  it.only('should return server sessions to the pool on `endSession`', {
+  it('should return server sessions to the pool on `endSession`', {
     metadata: { requires: { topology: 'single' } },
     test: function(done) {
       let sentIsMaster = false;