Bug 1467563 - Don't send any telemetry for rollbacks that were never rolled out r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D1591

toolkit/components/normandy/actions/PreferenceRollbackAction.jsm

@@ -24,8 +24,7 @@ class PreferenceRollbackAction extends BaseAction {
     const rollout = await PreferenceRollouts.get(rolloutSlug);
 
     if (!rollout) {
-      TelemetryEvents.sendEvent("unenrollFailed", "preference_rollback", rolloutSlug, {"reason": "rollout missing"});
-      this.log.info(`Cannot rollback ${rolloutSlug}: no rollout found with that slug`);
+      this.log.debug(`Rollback ${rolloutSlug} not applicable, skipping`);
       return;
     }
 

toolkit/components/normandy/test/browser/browser_actions_PreferenceRollbackAction.js

@@ -117,7 +117,7 @@ decorate_task(
   },
 );
 
-// Test that a rollback without a matching rollout
+// Test that a rollback without a matching rollout does not send telemetry
 decorate_task(
   PreferenceRollouts.withTestMock,
   withSendEventStub,
@@ -129,12 +129,7 @@ decorate_task(
     await action.runRecipe(recipe);
     await action.finalize();
 
-    Assert.deepEqual(
-      sendEventStub.args,
-      [["unenrollFailed", "preference_rollback", "missing-rollout", {reason: "rollout missing"}]],
-      "an unenrollFailure event should be sent",
-    );
-    // This is too common a case for an error, so it should be reported as success
+    Assert.deepEqual(sendEventStub.args, [], "an unenrollFailure event should not be sent");
     Assert.deepEqual(
       reportRecipeStub.args,
       [[recipe.id, Uptake.RECIPE_SUCCESS]],