Add goBack button to the participant-room view

src/app/participant-room/participant-room.component.html

@@ -31,4 +31,5 @@
       </mat-card-actions>
     </mat-card>
   </div>
+  <button mat-button color="primary" (click)="goBack()">Back</button>
 </div>

src/app/participant-room/participant-room.component.ts

 import { Component, OnInit } from '@angular/core';
+import { Room } from '../room';
+import { Location } from '@angular/common';
 
 @Component({
   selector: 'app-participant-room',
@@ -7,6 +9,8 @@ import { Component, OnInit } from '@angular/core';
 })
 export class ParticipantRoomComponent implements OnInit {
 
+  room: Room;
+
   roomId = '12 34 56 78';
   roomName = 'Test Room';
   roomDescription = 'Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore ' +
@@ -15,10 +19,13 @@ export class ParticipantRoomComponent implements OnInit {
     'tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea ' +
     'rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.';
 
-  constructor() {
+  constructor(private location: Location) {
   }
 
   ngOnInit() {
   }
 
+  goBack() {
+    this.location.back();
+  }
 }