Use Date.now.

debounce.js

@@ -1,5 +1,4 @@
 import isObject from './isObject.js';
-import now from './now.js';
 import toNumber from './toNumber.js';
 
 /** Error message constants. */
@@ -125,7 +124,7 @@ function debounce(func, wait, options) {
   }
 
   function timerExpired() {
-    const time = now();
+    const time = Date.now();
     if (shouldInvoke(time)) {
       return trailingEdge(time);
     }
@@ -154,11 +153,11 @@ function debounce(func, wait, options) {
   }
 
   function flush() {
-    return timerId === undefined ? result : trailingEdge(now());
+    return timerId === undefined ? result : trailingEdge(Date.now());
   }
 
   function debounced(...args) {
-    const time = now();
+    const time = Date.now();
     const isInvoking = shouldInvoke(time);
 
     lastArgs = args;

now.js

@@ -1,20 +0,0 @@
-import root from './_root.js';
-
-/**
- * Gets the timestamp of the number of milliseconds that have elapsed since
- * the Unix epoch (1 January 1970 00:00:00 UTC).
- *
- * @static
- * @since 2.4.0
- * @category Date
- * @returns {number} Returns the timestamp.
- * @example
- *
- * defer(function(stamp) {
- *   console.log(now() - stamp);
- * }, now());
- * // => Logs the number of milliseconds it took for the deferred invocation.
- */
-const now = () => root.Date.now();
-
-export default now;