message: fix(): correct so that google analytics page views gets registered once.
diff: import { Component } from '@stencil/core';
  -import { LocationSegments } from '@stencil/router';
  +import { LocationSegments, RouterHistory } from '@stencil/router';
  +
  @Component({
  tag: 'docs-root',
  styleUrl: 'root.css'
  })
  export class DocsRoot {
  + history: RouterHistory = null;
  +
  + setHistory = ({ history }: { history: RouterHistory }) => {
  + if (!this.history) {
  + this.history = history;
  + this.history.listen((location: LocationSegments) => {
  + (window as any).gtag('config', 'UA-44023830-1', { 'page_path': location.pathname + location.search });
  + });
  + }
  + }
  +
  render() {
  return (
  <stencil-router class="Layout" scrollTopOffset={0}>
  - <stencil-route style={{ display: 'none' }} routeRender={({ history }) =>
  - history.listen((location: LocationSegments) => {
  - (window as any).gtag('config', 'UA-44023830-1', {'page_path': location.pathname + location.search})
  - })
  - } />
  + <stencil-route style={{ display: 'none' }} routeRender={this.setHistory}/>
  <docs-header/>
  <docs-menu/>
  <stencil-route url="/docs/:page*" routeRender={props => (
  