bump(github.com/docker/spdystream):99515db39d3dad9607e0293f18152f3d59da76dc

Update spdystream to pick up a fix for a deadlock between writing data
and a connection closure.

Fixes #6490

Godeps/_workspace/src/github.com/docker/spdystream/connection.go

@@ -89,10 +89,25 @@ Loop:
 			if timer != nil {
 				timer.Stop()
 			}
+
+			// Start a goroutine to drain resetChan. This is needed because we've seen
+			// some unit tests with large numbers of goroutines get into a situation
+			// where resetChan fills up, at least 1 call to Write() is still trying to
+			// send to resetChan, the connection gets closed, and this case statement
+			// attempts to grab the write lock that Write() already has, causing a
+			// deadlock.
+			//
+			// See https://github.com/docker/spdystream/issues/49 for more details.
+			go func() {
+				for _ = range resetChan {
+				}
+			}()
+
 			i.writeLock.Lock()
 			close(resetChan)
 			i.resetChan = nil
 			i.writeLock.Unlock()
+
 			break Loop
 		}
 	}