Migrates audits/ to esm

Bug: 1006759
Change-Id: I3725508476779ed9002ace9f2c5bf57aaeb0b2c9
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/1928919
Reviewed-by: Tim van der Lippe <tvanderlippe@chromium.org>
Commit-Queue: Paul Lewis <aerotwist@chromium.org>
diff --git a/front_end/audits/AuditsReportRenderer.js b/front_end/audits/AuditsReportRenderer.js
index 1f89642..8ac9ad9 100644
--- a/front_end/audits/AuditsReportRenderer.js
+++ b/front_end/audits/AuditsReportRenderer.js
@@ -2,10 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+const MaxLengthForLinks = 40;
+
 /**
  * @override
  */
-Audits.ReportRenderer = class extends ReportRenderer {
+export class AuditsReportRenderer extends ReportRenderer {
   /**
    * @param {!Element} el Parent element to render the report into.
    * @param {!ReportRenderer.RunnerResultArtifacts=} artifacts
@@ -77,8 +79,8 @@
       const url = detailsItem.sourceUrl;
       const line = Number(detailsItem.sourceLine);
       const column = Number(detailsItem.sourceColumn);
-      const element = await Components.Linkifier.linkifyURL(
-          url, {lineNumber: line, column, maxLength: Audits.ReportRenderer.MaxLengthForLinks});
+      const element =
+          await Components.Linkifier.linkifyURL(url, {lineNumber: line, column, maxLength: MaxLengthForLinks});
       origElement.title = '';
       origElement.textContent = '';
       origElement.appendChild(element);
@@ -93,12 +95,12 @@
       el.classList.add('dark');
     }
   }
-};
+}
 
 /**
  * @override
  */
-Audits.ReportUIFeatures = class extends ReportUIFeatures {
+export class AuditsReportUIFeatures extends ReportUIFeatures {
   /**
    * @param {!DOM} dom
    */
@@ -182,10 +184,27 @@
   resetUIState() {
     this._resetUIState();
   }
-};
+}
+
+
+/* Legacy exported object */
+self.Audits = self.Audits || {};
+
+/* Legacy exported object */
+Audits = Audits || {};
+
+/**
+ * @constructor
+ */
+Audits.ReportRenderer = AuditsReportRenderer;
 
 /**
  * @const
  * @type {number}
  */
-Audits.ReportRenderer.MaxLengthForLinks = 40;
+Audits.ReportRenderer.MaxLengthForLinks = MaxLengthForLinks;
+
+/**
+ * @constructor
+ */
+Audits.ReportUIFeatures = AuditsReportUIFeatures;