Bug 1715129 - Collect telemetry on how many clients have Proton enabled. r=chutten data-review=chutten

Differential Revision: https://phabricator.services.mozilla.com/D117093

browser/base/content/metrics.yaml

@@ -0,0 +1,22 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+---
+$schema: moz://mozilla.org/schemas/glean/metrics/1-0-0
+
+browser.ui:
+  proton_enabled:
+    type: boolean
+    description: >
+      True if the Proton default theme is enabled.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1715129
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1715129#c3
+    data_sensitivity:
+      - technical
+    notification_emails:
+      - mconley@mozilla.com
+      - bwinton@mozilla.com
+    expires: "92"

browser/components/BrowserGlue.jsm

@@ -17,6 +17,8 @@ const { AppConstants } = ChromeUtils.import(
   "resource://gre/modules/AppConstants.jsm"
 );
 
+Cu.importGlobalProperties(["Glean"]);
+
 XPCOMUtils.defineLazyModuleGetters(this, {
   AboutNewTab: "resource:///modules/AboutNewTab.jsm",
   ActorManagerParent: "resource://gre/modules/ActorManagerParent.jsm",
@@ -2535,6 +2537,12 @@ BrowserGlue.prototype = {
         },
       },
 
+      {
+        task: () => {
+          this._collectProtonTelemetry();
+        },
+      },
+
       // WebDriver components (Remote Agent and Marionette) need to be
       // initialized as very last step.
       {
@@ -4225,6 +4233,14 @@ BrowserGlue.prototype = {
     }
   },
 
+  _collectProtonTelemetry() {
+    let protonEnabled = Services.prefs.getBoolPref(
+      "browser.proton.enabled",
+      true
+    );
+    Glean.browserUi.protonEnabled.set(protonEnabled);
+  },
+
   QueryInterface: ChromeUtils.generateQI([
     "nsIObserver",
     "nsISupportsWeakReference",

toolkit/components/glean/metrics_index.py

@@ -10,6 +10,7 @@ metrics_yamls = [
     "toolkit/components/glean/metrics.yaml",
     "toolkit/components/glean/test_metrics.yaml",
     "toolkit/mozapps/update/metrics.yaml",
+    "browser/base/content/metrics.yaml",
 ]
 
 # The list of all Glean pings.yaml files, relative to the top src dir.