Add firebase prefix to exp

Author: Athira M

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

@@ -59,7 +59,7 @@ export class Experiment {
   ): void {
     const customProperty: Record<string, string | null> = {};
     for (const [experimentId, experimentInfo] of experimentInfoMap.entries()) {
-      customProperty[experimentId] = experimentInfo.variantId;
+      customProperty[`firebase${experimentId}`] = experimentInfo.variantId;
     }
     this.addExperimentToAnalytics(customProperty);
   }
@@ -71,7 +71,7 @@ export class Experiment {
     const customProperty: Record<string, string | null> = {};
     for (const experimentId of currentActiveExperiments) {
       if (!experimentInfoMap.has(experimentId)) {
-        customProperty[experimentId] = null;
+        customProperty[`firebase${experimentId}`] = null;
       }
     }
     this.addExperimentToAnalytics(customProperty);

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

@@ -82,9 +82,9 @@ describe('Experiment', () => {
         expectedStoredExperiments
       );
       expect(analytics.setUserProperties).to.have.been.calledWith({
-        '_exp_3': '1',
-        '_exp_1': '2',
-        '_exp_2': '1'
+        'firebase_exp_3': '1',
+        'firebase_exp_1': '2',
+        'firebase_exp_2': '1'
       });
     });
 
@@ -110,7 +110,7 @@ describe('Experiment', () => {
         expectedStoredExperiments
       );
       expect(analytics.setUserProperties).to.have.been.calledWith({
-        '_exp_2': null
+        'firebase_exp_2': null
       });
     });
   });