Move header instantiation to base page

This way, all page objects have access to it without the need for
code duplication.

Author: Walmyr Filho

page-objects/base.js

@@ -1,4 +1,10 @@
+const HeaderComponent = require('./components/header')
+
 class Base {
+  constructor () {
+    this.header = new HeaderComponent()
+  }
+
   visit () {
     browser.get(this.relativeUrl)
   }

page-objects/destination.js

@@ -1,14 +1,12 @@
 const BasePage = require('./base')
 
-const HeaderComponent = require('./components/header')
 const DestinationComponent = require('./components/destination')
 
 const randomNumberBewtweenOneAnd = require('../utils/randomNumberBewtweenOneAndN')
 
 class Destination extends BasePage {
   constructor () {
     super()
-    this.header = new HeaderComponent()
     this.self = new DestinationComponent()
     this.relativeUrl = `/destinations/${randomNumberBewtweenOneAnd(15)}`
   }

page-objects/editDestination.js

@@ -1,6 +1,5 @@
 const BasePage = require('./base')
 
-const HeaderComponent = require('./components/header')
 const DestinationComponent = require('./components/destination')
 const FormComponent = require('./components/form')
 
@@ -9,7 +8,6 @@ const randomNumberBewtweenOneAnd = require('../utils/randomNumberBewtweenOneAndN
 class EditDestination extends BasePage {
   constructor () {
     super()
-    this.header = new HeaderComponent()
     this.self = new DestinationComponent()
     this.form = new FormComponent()
     this.relativeUrl = `/destinations/${randomNumberBewtweenOneAnd(15)}/edit`

page-objects/home.js

@@ -1,12 +1,10 @@
 const BasePage = require('./base')
 
-const HeaderComponent = require('./components/header')
 const TagsComponent = require('./components/tags')
 
 class Home extends BasePage {
   constructor () {
     super()
-    this.header = new HeaderComponent()
     this.tags = new TagsComponent()
     this.relativeUrl = '/'
   }

page-objects/tag.js

@@ -1,14 +1,12 @@
 const BasePage = require('./base')
 
-const HeaderComponent = require('./components/header')
 const DestinationsComponent = require('./components/destinations')
 
 const randomNumberBewtweenOneAnd = require('../utils/randomNumberBewtweenOneAndN')
 
 class Tag extends BasePage {
   constructor () {
     super()
-    this.header = new HeaderComponent()
     this.destinations = new DestinationsComponent()
     this.relativeUrl = `/tags/${randomNumberBewtweenOneAnd(5)}`
   }