Remove "force chunking" code from Arcanist
Remove "force chunking" code from Arcanist

Summary: Ref T7149. This was just for testing and is no longer required.

Test Plan: `grep`

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7149

Differential Revision: https://secure.phabricator.com/D12077

Symplicity/arcanist,calblueprint/arcanist,kevinseelbach/arcanist,Khan/arcanist,hach-que/arcanist,Khan/arcanist,sneakpeeq/arcanist,memsql/arcanist,r4nt/arcanist,wharris/arcanist,Symplicity/arcanist,fivestars/arcanist,folsom-labs/arcanist,codelabs-ch/arcanist,wxstars/arcanist,aik099/arcanist,hach-que/arcanist,KieranHayes/arcanist,calblueprint/arcanist,eSpark/arcanist,wikimedia/phabricator-arcanist,sneakpeeq/arcanist,eSpark/arcanist,r4nt/arcanist,wxstars/arcanist,wxstars/arcanist,phacility/arcanist,phacility/arcanist,aik099/arcanist,folsom-labs/arcanist,r4nt/arcanist,haskell-infra/arcanist,codelabs-ch/arcanist,hach-que/arcanist,chundongwang/arcanist,kevinseelbach/arcanist,codelabs-ch/arcanist,fivestars/arcanist,wikimedia/phabricator-arcanist,Khan/arcanist,sneakpeeq/arcanist,wharris/arcanist,sneakpeeq/arcanist,alexmv/arcanist,kevinseelbach/arcanist,r4nt/arcanist,wikimedia/phabricator-arcanist,chundongwang/arcanist,folsom-labs/arcanist,PageUpPeopleOrg/arcanist-patches,calblueprint/arcanist,chundongwang/arcanist,calblueprint/arcanist,wharris/arcanist,uber/arcanist,jra3/arcanist,haskell-infra/arcanist,PageUpPeopleOrg/arcanist-patches,uber/arcanist,coursera/arcanist,KieranHayes/arcanist,PageUpPeopleOrg/arcanist-patches,zhihu/arcanist,KieranHayes/arcanist,memsql/arcanist,zhihu/arcanist,folsom-labs/arcanist,zhihu/arcanist,chundongwang/arcanist,KieranHayes/arcanist,eSpark/arcanist,Symplicity/arcanist,alexmv/arcanist,zhihu/arcanist,phacility/arcanist,kevinseelbach/arcanist,hach-que/arcanist,phacility/arcanist,alexmv/arcanist,memsql/arcanist,wxstars/arcanist,Symplicity/arcanist,coursera/arcanist,wharris/arcanist,memsql/arcanist,uber/arcanist,haskell-infra/arcanist,uber/arcanist,codelabs-ch/arcanist,alexmv/arcanist,jra3/arcanist,jra3/arcanist,haskell-infra/arcanist,phacility/arcanist,eSpark/arcanist,fivestars/arcanist,coursera/arcanist,fivestars/arcanist,PageUpPeopleOrg/arcanist-patches,coursera/arcanist,aik099/arcanist,codelabs-ch/arcanist,wikimedia/phabricator-arcanist,Khan/arcanist,aik099/arcanist,jra3/arcanist