Prepare macrobenchmarks' e2e tests for firebase test lab (#63197)

dev/benchmarks/macrobenchmarks/android/app/build.gradle

@@ -41,6 +41,7 @@ android {
         targetSdkVersion 28
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 
     buildTypes {
@@ -54,3 +55,11 @@ android {
 flutter {
     source '../..'
 }
+
+dependencies {
+    testImplementation 'junit:junit:4.12'
+
+    // https://developer.android.com/jetpack/androidx/releases/test/#1.2.0
+    androidTestImplementation 'androidx.test:runner:1.2.0'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+}

dev/benchmarks/macrobenchmarks/android/app/src/androidTest/java/com/example/macrobenchmarks/MainActivityTest.java

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package com.example.macrobenchmarks;
+
+import androidx.test.rule.ActivityTestRule;
+import dev.flutter.plugins.e2e.FlutterTestRunner;
+import org.junit.Rule;
+import org.junit.runner.RunWith;
+
+@RunWith(FlutterTestRunner.class)
+public class MainActivityTest {
+  @Rule
+  public ActivityTestRule<MainActivity> rule = new ActivityTestRule<>(MainActivity.class, true, false);
+}