Fix feature defects if Web Experiments (#9327)

* Bug fixes

* yarn format fail

* update event name

* Ensure user property is parsed

* Add firebase prefix to exp

Author: athiramanu

packages/remote-config/src/abt/experiment.ts

@@ -39,7 +39,7 @@ export class Experiment {
     const currentActiveExperiments =
       (await this.storage.getActiveExperiments()) || new Set<string>();
     const experimentInfoMap = this.createExperimentInfoMap(latestExperiments);
-    this.addActiveExperiments(currentActiveExperiments, experimentInfoMap);
+    this.addActiveExperiments(experimentInfoMap);
     this.removeInactiveExperiments(currentActiveExperiments, experimentInfoMap);
     return this.storage.setActiveExperiments(new Set(experimentInfoMap.keys()));
   }
@@ -55,14 +55,11 @@ export class Experiment {
   }
 
   private addActiveExperiments(
-    currentActiveExperiments: Set<string>,
     experimentInfoMap: Map<string, FirebaseExperimentDescription>
   ): void {
     const customProperty: Record<string, string | null> = {};
     for (const [experimentId, experimentInfo] of experimentInfoMap.entries()) {
-      if (!currentActiveExperiments.has(experimentId)) {
-        customProperty[experimentId] = experimentInfo.variantId;
-      }
+      customProperty[`firebase${experimentId}`] = experimentInfo.variantId;
     }
     this.addExperimentToAnalytics(customProperty);
   }
@@ -74,7 +71,7 @@ export class Experiment {
     const customProperty: Record<string, string | null> = {};
     for (const experimentId of currentActiveExperiments) {
       if (!experimentInfoMap.has(experimentId)) {
-        customProperty[experimentId] = null;
+        customProperty[`firebase${experimentId}`] = null;
       }
     }
     this.addExperimentToAnalytics(customProperty);
@@ -89,7 +86,8 @@ export class Experiment {
     try {
       const analytics = this.analyticsProvider.getImmediate({ optional: true });
       if (analytics) {
-        analytics.setUserProperties({ properties: customProperty });
+        analytics.setUserProperties(customProperty);
+        analytics.logEvent(`set_firebase_experiment_state`);
       } else {
         this.logger.warn(`Analytics import failed`);
       }

packages/remote-config/test/abt/experiment.test.ts

@@ -41,7 +41,8 @@ describe('Experiment', () => {
       storage.getActiveExperiments = sinon.stub();
       storage.setActiveExperiments = sinon.stub();
       analyticsProvider.getImmediate = sinon.stub().returns({
-        setUserProperties: sinon.stub()
+        setUserProperties: sinon.stub(),
+        logEvent: sinon.stub()
       });
     });
 
@@ -81,7 +82,9 @@ describe('Experiment', () => {
         expectedStoredExperiments
       );
       expect(analytics.setUserProperties).to.have.been.calledWith({
-        properties: { '_exp_3': '1' }
+        'firebase_exp_3': '1',
+        'firebase_exp_1': '2',
+        'firebase_exp_2': '1'
       });
     });
 
@@ -107,7 +110,7 @@ describe('Experiment', () => {
         expectedStoredExperiments
       );
       expect(analytics.setUserProperties).to.have.been.calledWith({
-        properties: { '_exp_2': null }
+        'firebase_exp_2': null
       });
     });
   });