Bug 1829140 - Avoid collecting some telemetry when MOZ_TELEMETRY_REPORTING is not set. r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D176060

browser/modules/BrowserUsageTelemetry.jsm

@@ -1175,8 +1175,15 @@ let BrowserUsageTelemetry = {
 
   // Reports the number of Firefox profiles on this machine to telemetry.
   async reportProfileCount() {
-    if (AppConstants.platform != "win") {
+    if (
+      AppConstants.platform != "win" ||
+      !AppConstants.MOZ_TELEMETRY_REPORTING
+    ) {
       // This is currently a windows-only feature.
+      // Also, this function writes directly to disk, without using the usual
+      // telemetry recording functions. So we excplicitly check if telemetry
+      // reporting was disabled at compile time, and we do not do anything in
+      // case.
       return;
     }
 

toolkit/xre/nsAppRunner.cpp

@@ -2695,7 +2695,11 @@ static ReturnAbortOnError ProfileLockedDialog(nsIFile* aProfileDir,
   rv = xpcom.Initialize();
   NS_ENSURE_SUCCESS(rv, rv);
 
+#if defined(MOZ_TELEMETRY_REPORTING)
+  // We cannot check if telemetry has been disabled by the user, yet.
+  // So, rely on the build time settings, instead.
   mozilla::Telemetry::WriteFailedProfileLock(aProfileDir);
+#endif
 
   rv = xpcom.SetWindowCreator(aNative);
   NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);