Only remove post from stream after successful response

Pass destroyModel from post control view to post view
and don't listen to the remove event in the post view
anymore. The `remove` function will be called from the
base view.

Fixes #5445

app/assets/javascripts/app/views/post_controls_view.js

@@ -76,6 +76,10 @@ app.views.PostControls = app.views.Base.extend({
     $.post(Routes.postParticipation(this.model.get("id")), {_method: "delete"}, function() {
       this.model.set({participation: false});
     }.bind(this));
+  },
+
+  destroyModel: function() {
+    this.post.destroyModel();
   }
 });
 // @license-end

app/assets/javascripts/app/views/stream_post_views.js

@@ -33,7 +33,6 @@ app.views.StreamPost = app.views.Post.extend({
       var personId = this.model.get("author").id;
       app.events.on("person:block:" + personId, this.remove, this);
     }
-    this.model.on("remove", this.remove, this);
     //subviews
     this.commentStreamView = new app.views.CommentStream({model : this.model});
     this.oEmbedView = new app.views.OEmbed({model : this.model});

app/assets/stylesheets/stream_element.scss

@@ -4,7 +4,8 @@
     margin: 0px;
   }
   &.deleting {
-    > .media { opacity: 0.3; }
+    opacity: .3;
+
     .control-icons { display: none !important; }
   }
 }

spec/javascripts/app/views/post_controls_view_spec.js

@@ -74,12 +74,15 @@ describe("app.views.PostControls", function() {
     });
 
     it("calls destroyModel when removing a post", function() {
-      spyOn(app.views.PostControls.prototype, "destroyModel");
+      spyOn(app.views.PostControls.prototype, "destroyModel").and.callThrough();
+      spyOn(app.views.Post.prototype, "destroyModel");
       app.currentUser = new app.models.User(this.model.attributes.author);
-      this.view = new app.views.PostControls({model: this.model});
+      this.postView = new app.views.Post({model: this.model});
+      this.view = new app.views.PostControls({model: this.model, post: this.postView});
       this.view.render();
       this.view.$(".remove_post.delete").click();
       expect(app.views.PostControls.prototype.destroyModel).toHaveBeenCalled();
+      expect(app.views.Post.prototype.destroyModel).toHaveBeenCalled();
     });
 
     it("calls hidePost when hiding a post", function() {