[e2e] Use SettableFutures instead of CompletableFuture

This works better for internal use cases.

Author: jiahaog

packages/e2e/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.6.0
+
+* **Breaking change** `E2EPlugin` exports a `ListenableFuture` for `testResults`.
+
 ## 0.5.0+1
 
 * Fixed the device pixel ratio problem.

packages/e2e/android/build.gradle

@@ -33,11 +33,11 @@ android {
     }
     dependencies {
         api 'junit:junit:4.12'
-        implementation 'net.sourceforge.streamsupport:android-retrofuture:1.7.2'
 
         // https://developer.android.com/jetpack/androidx/releases/test/#1.2.0
         api 'androidx.test:runner:1.2.0'
         api 'androidx.test:rules:1.2.0'
         api 'androidx.test.espresso:espresso-core:3.2.0'
+        api 'com.google.guava:guava:28.1-android'
     }
 }

packages/e2e/android/src/main/java/dev/flutter/plugins/e2e/E2EPlugin.java

@@ -5,6 +5,8 @@
 package dev.flutter.plugins.e2e;
 
 import android.content.Context;
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.common.util.concurrent.SettableFuture;
 import io.flutter.embedding.engine.plugins.FlutterPlugin;
 import io.flutter.plugin.common.BinaryMessenger;
 import io.flutter.plugin.common.MethodCall;
@@ -13,13 +15,14 @@
 import io.flutter.plugin.common.MethodChannel.Result;
 import io.flutter.plugin.common.PluginRegistry.Registrar;
 import java.util.Map;
-import java9.util.concurrent.CompletableFuture;
 
 /** E2EPlugin */
 public class E2EPlugin implements MethodCallHandler, FlutterPlugin {
   private MethodChannel methodChannel;
 
-  public static CompletableFuture<Map<String, String>> testResults = new CompletableFuture<>();
+  private static final SettableFuture<Map<String, String>> testResultsSettable =
+      SettableFuture.create();
+  public static final ListenableFuture<Map<String, String>> testResults = testResultsSettable;
 
   private static final String CHANNEL = "plugins.flutter.io/e2e";
 
@@ -49,7 +52,7 @@ public void onDetachedFromEngine(FlutterPluginBinding binding) {
   public void onMethodCall(MethodCall call, Result result) {
     if (call.method.equals("allTestsFinished")) {
       Map<String, String> results = call.argument("results");
-      testResults.complete(results);
+      testResultsSettable.set(results);
       result.success(null);
     } else {
       result.notImplemented();