function toggleBreakpoint(type)
        {
            if (!nodeBreakpoints[type])
                this._setBreakpoint(node, type, true);
            else
                this._removeBreakpoint(node, type);
            this._saveBreakpoints();
        }
@param {!DOMDebuggerAgent.DOMBreakpointType} type
@this {WebInspector.DOMBreakpointsSidebarPane}