Bug 1499710 - Remove autohideOnDestroy trait; r=ochameau

Depends on D8987

Differential Revision: https://phabricator.services.mozilla.com/D8988

--HG--
extra : moz-landing-system : lando

devtools/client/framework/toolbox.js

@@ -2767,14 +2767,6 @@ Toolbox.prototype = {
       this._inspector.destroy();
 
       if (this._highlighter) {
-        // Note that if the toolbox is closed, this will work fine, but will fail
-        // in case the browser is closed and will trigger a noSuchActor message.
-        // We ignore the promise that |_hideBoxModel| returns, since we should still
-        // proceed with the rest of destruction if it fails.
-        // FF42+ now does the cleanup from the actor.
-        if (!this.highlighter.traits.autoHideOnDestroy) {
-          this.highlighterUtils.unhighlight();
-        }
         await this._highlighter.destroy();
       }
       if (this._selection) {

devtools/server/actors/highlighters.js

@@ -113,9 +113,6 @@ exports.HighlighterActor = protocol.ActorClassWithSpec(highlighterSpec, {
   form: function() {
     return {
       actor: this.actorID,
-      traits: {
-        autoHideOnDestroy: true
-      }
     };
   },