LPS-51939

$ ant format-source
Buildfile: d:\repo\portal\portal-impl\build.xml

format-source:
     [copy] Copying 2 files to d:\repo\portal\portal-impl\classes
     [java] Loading file:/D:/repo/portal/portal-impl/classes/system.properties
     [java] Loading file:/D:/repo/portal/portal-impl/classes/portal.properties

BUILD SUCCESSFUL
Total time: 1 minute 7 seconds

I renamed isRemoveNotificationEvent to isExpired because that is what the internal logic of that method actually checks. I also removed a lot of duplicate logic because that convenience methods can easily be implemented at the access point (ChannelHubManagerUtil) with a for loop instead of duplicating logic all the way into ChannelImpl.

This doesn't necessarily fix a bug, it just makes maintenance cleaner.