76c670075b
https://build.spring.io/browse/INT-FATS5IC-685/ Even if we stop `SourcePollingChannelAdapter`, the task on the fly is still going to be executed. This way we may have extra calls to our logic. * Use `CopyOnWriteArrayList` for the `sessionSources` to avoid `ConcurrentModificationException` during this collection read in the tests **Cherry-pick to 5.0.x**