_initBubbleSignals changes v1

    _initSomething: function(object, signal, interval) {
        let sourceId = null;
        let signalId = object.connect(signal, (function() {
            if (sourceId)
                Mainloop.source_remove(sourceId);
            else
                this.hideBubble();

            sourceId = Mainloop.timeout_add(interval, (function() {
                this.showBubble();
                sourceId = null;
            }).bind(this));
        }).bind(this));

        Utils.once(this.bubble, 'closed', (function() {
            if (!sourceId)
                object.disconnect(signalId);
        }).bind(this));

        Utils.once(this, 'notify::selected', (function() {
            if (sourceId) {
                Mainloop.source_remove(sourceId);
                object.disconnect(signalId);
            }
        }).bind(this));
    },

    _initBubbleSignals: function() {
        // This is done to get just one marker selected at any time regardless
        // of the layer to which it belongs so we can get only one visible bubble
        // at any time. We do this for markers in different layers because for
        // markers in the same layer, ChamplainMarkerLayer single selection mode
        // does the job.
        this._mapView.onSetMarkerSelected(this);

        let markerSelectedSignalId = this._mapView.connect('marker-selected', (function(mapView, selectedMarker) {
            if (this.get_parent() != selectedMarker.get_parent())
                this.selected = false;
        }).bind(this));

        this._initSomething(this._view, 'notify::zoom-level', 500);
        this._initSomething(this._view, 'notify::size', 0);

        let buttonPressSignalId = this._view.connect('button-press-event',
                                                     this.set_selected.bind(this, false));
        let goingToSignalId = this._mapView.connect('going-to',
                                                    this.set_selected.bind(this, false));
        let parentSetSignalId = this.connect('parent-set',
                                             this.set_selected.bind(this, false));
        let dragMotionSignalId = this.connect('drag-motion',
                                              this.set_selected.bind(this, false));

        Utils.once(this.bubble, 'closed', (function() {
            this._mapView.disconnect(markerSelectedSignalId);
            this._view.disconnect(buttonPressSignalId);
            this._mapView.disconnect(goingToSignalId);
            this.disconnect(parentSetSignalId);
            this.disconnect(dragMotionSignalId);

            this._bubble.destroy();
            delete this._bubble;
        }).bind(this));
    },