DevTools: [lighthouse] Implement performance metrics filmstrip

third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js

Index: third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js
diff --git a/third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js b/third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js
index a1a4afad0a2442d663df1198d80e8ad6d36a97db..993a8b766e2ae04145ab0d3093d3c537586569e1 100644
--- a/third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js
+++ b/third_party/WebKit/Source/devtools/front_end/audits2_worker/Audits2Service.js
@@ -45,9 +45,18 @@ var Audits2Service = class {
     });
 
     return Promise.resolve()
-      .then(_ => self.runLighthouseInWorker(this, params.url, undefined, params.categoryIDs))
-      .then(/** @type {!ReportRenderer.ReportJSON} */ result => result)
-      .catchException(null);
+        .then(_ => self.runLighthouseInWorker(this, params.url, undefined, params.categoryIDs))
+        .then(/** @type {!ReportRenderer.ReportJSON} */ result => {
+          // Filter out artifacts except for screenshots in traces to minimize report size.
+          var traces = result['artifacts']['traces'];
+          for (var pass in traces) {
+            traces[pass]['traceEvents'] =
+                traces[pass]['traceEvents'].filter(e => e['cat'] === 'disabled-by-default-devtools.screenshot');
+          }
+          result['artifacts'] = {traces: traces};
+          return result;
+        })
+        .catchException(null);
   }
 
   /**