Remove DOM remove() polyfills

Remove polyfill functions for Element, CharacterData and DocumentType
classes, as these methods are all Baseline Widely Available. Also get
rid of redundant IIFE for the Math "polyfills".

src/js/core/polyfills.js

@@ -1,38 +0,0 @@
-function mathPolyfills() {
-    // Converts from degrees to radians.
-    Math.radians = function (degrees) {
-        return (degrees * Math.PI) / 180.0;
-    };
-
-    // Converts from radians to degrees.
-    Math.degrees = function (radians) {
-        return (radians * 180.0) / Math.PI;
-    };
-}
-
-function domPolyfills() {
-    // from:https://github.com/jserz/js_piece/blob/master/DOM/ChildNode/remove()/remove().md
-    (function (arr) {
-        arr.forEach(function (item) {
-            if (item.hasOwnProperty("remove")) {
-                return;
-            }
-            Object.defineProperty(item, "remove", {
-                configurable: true,
-                enumerable: true,
-                writable: true,
-                value: function remove() {
-                    this.parentNode.removeChild(this);
-                },
-            });
-        });
-    })([Element.prototype, CharacterData.prototype, DocumentType.prototype]);
-}
-
-function initPolyfills() {
-    mathPolyfills();
-    domPolyfills();
-}
-
-// Other polyfills
-initPolyfills();

src/js/core/polyfills.ts

@@ -0,0 +1,9 @@
+// Converts from degrees to radians.
+Math.radians = function (degrees: number): number {
+    return (degrees * Math.PI) / 180.0;
+};
+
+// Converts from radians to degrees.
+Math.degrees = function (radians: number): number {
+    return (radians * 180.0) / Math.PI;
+};