Portable implementation of fullscreen JS methods

platypush/backend/http/static/js/utils.js

@@ -1,9 +1,34 @@
 function enterFullScreen() {
-    return document.getElementsByTagName('body')[0].requestFullscreen();
+    const body = document.getElementsByTagName('body')[0];
+    if (body.requestFullscreen()) {
+        return body.requestFullscreen();
+    } else if (body.msRequestFullscreen()) {
+        return body.msRequestFullscreen();
+    } else if (body.mozRequestFullScreen()) {
+        return body.mozRequestFullScreen();
+    } else if (body.webkitRequestFullscreen()) {
+        return body.webkitRequestFullscreen();
+    } else {
+        console.warn('This browser does not support fullscreen mode');
+    }
+
+    // The day will come when browser developers will have to pay web developers
+    // back for all the time wasted to write such crappy portable code. A two-lines
+    // function becomes a 10-lines function just because they can't talk to
+    // one another before implementing sh*t.
 }
 
 function exitFullScreen() {
-    const self = this;
-    return document.exitFullscreen();
+    if (document.exitFullscreen()) {
+        return document.exitFullscreen();
+    } else if (document.msExitFullscreen()) {
+        return document.msExitFullscreen();
+    } else if (document.mozCancelFullScreen()) {
+        return document.mozCancelFullScreen();
+    } else if (document.webkitExitFullscreen()) {
+        return document.webkitExitFullscreen();
+    } else {
+        console.warn('This browser does not support fullscreen mode');
+    }
 }