Bug 1818512 - mirror browser.engagement.profile_count to glean r=chutten

Differential Revision: https://phabricator.services.mozilla.com/D170786

browser/modules/test/unit/test_ProfileCounter.js

@@ -86,6 +86,10 @@ function reset(resetFile = true) {
 
 function setup() {
   reset();
+  // FOG needs a profile directory to put its data in.
+  do_get_profile();
+  // Initialize FOG so we can test the FOG version of profile count
+  Services.fog.initializeFOG();
 
   BrowserUsageTelemetry.Policy.readProfileCountFile = async path => {
     if (!gProfileCounterFilePath) {
@@ -147,6 +151,7 @@ function checkSuccess(profilesReported, rawCount = profilesReported) {
     profilesReported,
     "The value reported to telemetry should be the expected profile count"
   );
+  Assert.equal(rawCount, Glean.browser.engagement.profile_count.testGetValue());
 }
 
 function checkError() {