Bug 1500072 - Add metrics test for netmonitor;r=ochameau

Depends on D19638

Differential Revision: https://phabricator.services.mozilla.com/D19639

--HG--
rename : devtools/client/framework/test/metrics/browser_metrics_webconsole.ini => devtools/client/framework/test/metrics/browser_metrics_netmonitor.ini
rename : devtools/client/framework/test/metrics/browser_metrics_webconsole.js => devtools/client/framework/test/metrics/browser_metrics_netmonitor.js
extra : moz-landing-system : lando

devtools/client/framework/moz.build

@@ -7,6 +7,7 @@
 BROWSER_CHROME_MANIFESTS += [
     'test/browser.ini',
     'test/metrics/browser_metrics_inspector.ini',
+    'test/metrics/browser_metrics_netmonitor.ini',
     'test/metrics/browser_metrics_webconsole.ini',
 ]
 XPCSHELL_TESTS_MANIFESTS += ['test/unit/xpcshell.ini']

devtools/client/framework/test/metrics/browser_metrics_netmonitor.ini

@@ -0,0 +1,12 @@
+[DEFAULT]
+tags = devtools
+subsuite = devtools
+support-files =
+  head.js
+  !/devtools/client/shared/test/shared-head.js
+  !/devtools/client/shared/test/telemetry-test-helpers.js
+
+# Each metrics tests is loaded in a separate .ini file. This way the test is executed
+# individually, without any other test being executed before or after.
+[browser_metrics_netmonitor.js]
+skip-if = os != 'linux' || debug || asan # Results should be platform agnostic - only run on linux64-opt

devtools/client/framework/test/metrics/browser_metrics_netmonitor.js

@@ -0,0 +1,31 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/* import-globals-from ../../../shared/test/shared-head.js */
+
+/**
+ * This test records the number of modules loaded by DevTools, as well as the total count
+ * of characters in those modules, when opening the netmonitor. These metrics are
+ * retrieved by perfherder via logs.
+ */
+
+const TEST_URL = "data:text/html;charset=UTF-8,<div>Netmonitor modules load test</div>";
+
+add_task(async function() {
+  const toolbox = await openNewTabAndToolbox(TEST_URL, "netmonitor");
+  const panel = toolbox.getCurrentPanel();
+
+  // Retrieve the browser loader dedicated to the Netmonitor.
+  const netmonitorLoader = panel.panelWin.getBrowserLoaderForWindow();
+  const loaders = [loader.provider.loader, netmonitorLoader.loader];
+
+  runMetricsTest({
+    filterString: "devtools/client/netmonitor",
+    loaders,
+    panelName: "netmonitor",
+  });
+});