[matchbrackets addon] Clear matched brackets when the addon is turned off
[matchbrackets addon] Clear matched brackets when the addon is turned off

Closes #4128

ficristo/CodeMirror,alur/CodeMirror,kerabromsmu/CodeMirror,grzegorzmazur/CodeMirror,jayaprabhakar/CodeMirror,TDaglis/CodeMirror,ejgallego/CodeMirror,crazy4chrissi/CodeMirror,rrandom/CodeMirror,INTELOGIE/CodeMirror,mizchi/CodeMirror,wingify/CodeMirror,mizchi/CodeMirror,codio/CodeMirror,jayaprabhakar/CodeMirror,kerabromsmu/CodeMirror,sourcelair/CodeMirror,rrandom/CodeMirror,jkaplon/CodeMirror,ficristo/CodeMirror,hackmdio/CodeMirror,nightwing/CodeMirror,jkaplon/CodeMirror,dperetti/CodeMirror,pabloferz/CodeMirror,xeronith/CodeMirror,jayaprabhakar/CodeMirror,adobe/CodeMirror2,notepadqq/CodeMirror,grzegorzmazur/CodeMirror,schanzer/CodeMirror,schanzer/CodeMirror,nightwing/CodeMirror,adobe/CodeMirror2,notepadqq/CodeMirror,hackmdio/CodeMirror,codio/CodeMirror,jkaplon/CodeMirror,wingify/CodeMirror,crazy4chrissi/CodeMirror,pabloferz/CodeMirror,dperetti/CodeMirror,dperetti/CodeMirror,xeronith/CodeMirror,SidPresse/CodeMirror,wingify/CodeMirror,notepadqq/CodeMirror,mtaran-google/CodeMirror,adobe/CodeMirror2,MarcelGerber/CodeMirror,ejgallego/CodeMirror,mizchi/CodeMirror,grzegorzmazur/CodeMirror,thomasjm/CodeMirror,hackmdio/CodeMirror,SidPresse/CodeMirror,rrandom/CodeMirror,nightwing/CodeMirror,alur/CodeMirror,alur/CodeMirror,crazy4chrissi/CodeMirror,xeronith/CodeMirror,MarcelGerber/CodeMirror,sourcelair/CodeMirror,namin/CodeMirror,namin/CodeMirror,mtaran-google/CodeMirror,thomasjm/CodeMirror,mtaran-google/CodeMirror,thomasjm/CodeMirror,namin/CodeMirror,SidPresse/CodeMirror,TDaglis/CodeMirror,TDaglis/CodeMirror,ficristo/CodeMirror,pabloferz/CodeMirror,sourcelair/CodeMirror,schanzer/CodeMirror,kerabromsmu/CodeMirror,INTELOGIE/CodeMirror,MarcelGerber/CodeMirror,INTELOGIE/CodeMirror,codio/CodeMirror,ejgallego/CodeMirror