CCA: Use Date.now() for consistency

Bug: None
Test: CQ
Change-Id: I66602b8876bc43b0ec288d1bc4e8d7420ba3242d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2554251
Auto-Submit: Shik Chen <shik@chromium.org>
Commit-Queue: Inker Kuo <inker@chromium.org>
Reviewed-by: Inker Kuo <inker@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830096}

chromeos/components/camera_app_ui/resources/js/untrusted_ga_helper.js

@@ -38,7 +38,7 @@ async function initGA(id, clientId, shouldAddFakeHistory, setClientIdCallback) {
     i['GoogleAnalyticsObject'] = r;
     i[r] = i[r] || function(...args) {
       (i[r].q = i[r].q || []).push(args);
-    }, i[r].l = new Date().getTime();
+    }, i[r].l = Date.now();
     const a = s.createElement(o);
     const m = s.getElementsByTagName(o)[0];
     a['async'] = 1;