Use ModuleHandler Interface In AgentHelper

Looks good and a simple fix that won't break anything: should this issue be in needs review @ipumpkin?

@mrdalesmith ，when use this module with Hook Event Dispatcher → module, will broken site by this issue.

I'm not sure that's an answer to my question? I was asking about the status of this ticket currently being "active", which means it isn't ready to be reviewed or merged.

ready for review, (●'◡'●)

LGTM then :)

There is the same issue when using Hux → module. +1 for using interface instead.

Looks good, getting merged.