chore(addon): Fixes #1521 - Disable ExperimentProvider for SHIELD stu…

…dy users.

addon/ActivityStreams.js

@@ -99,7 +99,9 @@ ActivityStreams.prototype = {
     this._initializeAppURLHider();
     this._initializeMemoizer();
 
-    this._experimentProvider.init();
+    if (!this.options.shield_variant) {
+      this._experimentProvider.init();
+    }
     this._tabTracker.init(this.appURLs, this._memoized, this._experimentProvider.experimentId);
     this._initializeSearchProvider();
     this._initializePreviewProvier(this._experimentProvider, this._metadataStore, this._tabTracker);

test/test-ExperimentProvider.js

@@ -11,4 +11,31 @@ exports["test ActivityStreams has experimentProvider instance"] = assert => {
   as.unload();
 };
 
+exports["test ActivityStreams doesn't init experimentProvider"] = assert => {
+  const as = getTestActivityStream({
+    experiments: {
+      foo: {
+        name: "Foo Test",
+        description: "A test about foo",
+        control: {
+          value: false,
+          description: "Foo is 42 by default"
+        },
+        variant: {
+          id: "foo_01",
+          value: true,
+          threshold: 0.5,
+          description: "Twice the foo"
+        }
+      }
+    },
+    rng: () => 0.1,
+    shield_variant: "test"
+  });
+  assert.ok(as._experimentProvider instanceof ExperimentProvider, "should have _experimentProvider");
+  assert.equal(as._experimentProvider.experimentId, null, "should be null if shield variant set");
+  assert.deepEqual(as._experimentProvider.data, {}, "should have empty .data");
+  as.unload();
+};
+
 test.run(exports);