Update gUM still capture sample to current API

Use the latest API for capture using getUserMedia()

Author: a2sheppy

s/webrtc-capturestill/capture.js

@@ -25,29 +25,14 @@
     photo = document.getElementById('photo');
     startbutton = document.getElementById('startbutton');
 
-    navigator.getMedia = ( navigator.getUserMedia ||
-                           navigator.webkitGetUserMedia ||
-                           navigator.mozGetUserMedia ||
-                           navigator.msGetUserMedia);
-
-    navigator.getMedia(
-      {
-        video: true,
-        audio: false
-      },
-      function(stream) {
-        if (navigator.mozGetUserMedia) {
-          video.mozSrcObject = stream;
-        } else {
-          var vendorURL = window.URL || window.webkitURL;
-          video.src = vendorURL.createObjectURL(stream);
-        }
-        video.play();
-      },
-      function(err) {
-        console.log("An error occured! " + err);
-      }
-    );
+    navigator.mediaDevices.getUserMedia({video: true, audio: false})
+    .then(function(stream) {
+      video.srcObject = stream;
+      video.play();
+    })
+    .catch(function(err) {
+      console.log("An error occurred: " + err);
+    });
 
     video.addEventListener('canplay', function(ev){
       if (!streaming) {