Support Fullscreen detection

feature.js

@@ -205,6 +205,18 @@
     // Test if Picture element is supported
     pictureElement : ("HTMLPictureElement" in window),
 
+    // Test if fullscreen is supported
+    fullscreen : (function(el) {
+      var test = ["requestFullscreen", "webkitRequestFullscreen", 
+        "webkitRequestFullScreen" , "mozRequestFullScreen", "msRequestFullscreen"];
+        for (var prop in test) {
+          if (el[test[prop]]) {
+            return true;
+          }
+        }
+        return false;
+    })(util.create("video")),
+
     // Run all the tests and add supported classes
     testAll : function() {
       var classes = " js";

tests/index.html

@@ -101,6 +101,8 @@ <h4>Context Menu</h4>
         <menuitem label="FEATURE.JS TEST MENU ITEM" onclick="window.location.reload();"></menuitem>
       </menu>
 
+      <h4>Fullscreen</h4>
+      <div class="test" id="fullscreen"></div>
 
     </div>
     <script>
@@ -166,6 +168,7 @@ <h4>Context Menu</h4>
       log(feature.webGL, "WebGL");
       log(feature.cors, "CORS");
       log(feature.touch, "Touch");
+      log(feature.fullscreen, "Fullscreen");
 
       // 3D Transforms
       if (feature.css3Dtransform) {
@@ -355,6 +358,12 @@ <h4>Context Menu</h4>
         needsContextMenu.className += " active";
       }
 
+      // Fullscreen
+      if(feature.fullscreen) {
+        var needsFullscreen = document.getElementById("fullscreen");
+        needsFullscreen.className += " active";
+      }
+
     </script>
   </body>
 </html>