don't render json in a slave block
don't render json in a slave block

it might go to a discussion topic json, which will implicitly mark
it as read

Change-Id: Id4d3a62902852d130fa04aea8e2fa2402f760fd7
Reviewed-on: https://gerrit.instructure.com/15975
Reviewed-by: Brian Palmer <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@instructure.com>
QA-Review: Brian Palmer <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@instructure.com>
Tested-by: Brian Palmer <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@instructure.com>

Unow/canvas-lms,sfu/canvas-lms,usmschuck/canvas,efrj/canvas-lms,sdeleon28/canvas-lms,jay3126/canvas-lms,arrivu/jigsaw-lms,skmezanul/canvas-lms,antoniuslin/canvas-lms,arrivu/arrivu-lms,venturehive/canvas-lms,sdeleon28/canvas-lms,Jyaasa/canvas-lms,shidao-fm/canvas-lms,roxolan/canvas-lms,leftplusrightllc/canvas-lms,venturehive/canvas-lms,jay3126/canvas-lms,kyroskoh/canvas-lms,samuels410/greatlakes-lms,wrdsb/canvas-lms,Rvor/canvas-lms,usmschuck/canvas,Unow/canvas-lms,va7map/canvas-lms,wye0220/shindig-canvas,landonwilkins/canvas-lms,nditech/red-innovadores-lms,sli7246/canvas_branch,sli7246/canvas_branch,tgroshon/canvas-lms,kyroskoh/canvas-lms,redconfetti/canvas-lms,redconfetti/canvas-lms,Rvor/canvas-lms,ShreniiNepal/shrenii_lmp,whalejasmine/canvas-lms,SwinburneOnline/canvas-lms,parbros/red-innovadores-lms,kyroskoh/canvas-lms,va7map/canvas-lms,sfu/canvas-lms,arrivu/arrivu-lms,utkarshx/canvas-lms,tgroshon/canvas-lms,tgroshon/canvas-lms,wye0220/shindig-canvas,SwinburneOnline/canvas-lms,landonwilkins/canvas-lms,HotChalk/canvas-lms,SwinburneOnline/canvas-lms,ShreniiNepal/shrenii_lmp,sfu/canvas-lms,va7map/canvas-lms,sfu/canvas-lms,roxolan/canvas-lms,efrj/canvas-lms,loganrun/pincan,roxolan/canvas-lms,leftplusrightllc/canvas-lms,djbender/canvas-lms,sdeleon28/canvas-lms,greyhwndz/canvas-lms,HotChalk/canvas-lms,Unow/canvas-lms,tgroshon/canvas-lms,skmezanul/canvas-lms,arrivu/qibla-ecampus,SwinburneOnline/canvas-lms,fronteerio/canvas-lms,rup/Tarrax,jay3126/canvas-lms,whalejasmine/canvas-lms,Unow/ins,wimemx/Canvas,parbros/red-innovadores-lms,shidao-fm/canvas-lms,antoniuslin/canvas-lms,fronteerio/canvas-lms,djbender/canvas-lms,arrivu/qibla-ecampus,juoni/canvas-lms,arrivu/arrivu-lms,ShreniiNepal/shrenii_lmp,greyhwndz/canvas-lms,skmezanul/canvas-lms,utkarshx/canvas-lms,sdeleon28/canvas-lms,grahamb/canvas-lms,roxolan/canvas-lms,parbros/red-innovadores-lms,grahamb/canvas-lms,sfu/canvas-lms,va7map/canvas-lms,usmschuck/canvas,loganrun/pincan,whalejasmine/canvas-lms,wrdsb/canvas-lms,kyroskoh/canvas-lms,arrivu/qibla-ecampus,juoni/canvas-lms,arrivu/jigsaw-lms,shidao-fm/canvas-lms,nditech/red-innovadores-lms,greyhwndz/canvas-lms,wrdsb/canvas-lms,nditech/red-innovadores-lms,arrivu/hoodemo,wrdsb/canvas-lms,djbender/canvas-lms,grahamb/canvas-lms,Jyaasa/canvas-lms,wimemx/Canvas,Jyaasa/canvas-lms,sli7246/canvas_branch,skmezanul/canvas-lms,Rvor/canvas-lms,samuels410/greatlakes-lms,antoniuslin/canvas-lms,efrj/canvas-lms,redconfetti/canvas-lms,landonwilkins/canvas-lms,sfu/canvas-lms,HotChalk/canvas-lms,djbender/canvas-lms,rup/Tarrax,jay3126/canvas-lms,utkarshx/canvas-lms,grahamb/canvas-lms,arrivu/hoodemo,Rvor/canvas-lms,wimemx/Canvas,wye0220/shindig-canvas,Jyaasa/canvas-lms,merichar/canvas-lms,juoni/canvas-lms,samuels410/greatlakes-lms,arrivu/hoodemo,merichar/canvas-lms,usmschuck/canvas,leftplusrightllc/canvas-lms,arrivu/jigsaw-lms,leftplusrightllc/canvas-lms,nditech/red-innovadores-lms,efrj/canvas-lms,landonwilkins/canvas-lms,fronteerio/canvas-lms,loganrun/pincan,redconfetti/canvas-lms,ShreniiNepal/shrenii_lmp,whalejasmine/canvas-lms,utkarshx/canvas-lms,rup/Tarrax,sfu/canvas-lms,Unow/ins,fronteerio/canvas-lms,venturehive/canvas-lms,Unow/ins,juoni/canvas-lms,antoniuslin/canvas-lms,merichar/canvas-lms,grahamb/canvas-lms,shidao-fm/canvas-lms,HotChalk/canvas-lms,venturehive/canvas-lms,greyhwndz/canvas-lms,samuels410/greatlakes-lms