Migrate some more integration tests to Android embedding v2 (#48532)

diff --git a/dev/integration_tests/image_loading/android/app/src/main/AndroidManifest.xml b/dev/integration_tests/image_loading/android/app/src/main/AndroidManifest.xml
index 3002b1b..5ffd3d3 100644
--- a/dev/integration_tests/image_loading/android/app/src/main/AndroidManifest.xml
+++ b/dev/integration_tests/image_loading/android/app/src/main/AndroidManifest.xml
@@ -28,5 +28,10 @@
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+    <!-- Don't delete the meta-data below.
+         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
     </application>
 </manifest>
diff --git a/dev/integration_tests/image_loading/android/app/src/main/java/com/yourcompany/platforminteraction/MainActivity.java b/dev/integration_tests/image_loading/android/app/src/main/java/com/yourcompany/platforminteraction/MainActivity.java
index 37bd362..d701d4e 100644
--- a/dev/integration_tests/image_loading/android/app/src/main/java/com/yourcompany/platforminteraction/MainActivity.java
+++ b/dev/integration_tests/image_loading/android/app/src/main/java/com/yourcompany/platforminteraction/MainActivity.java
@@ -4,15 +4,14 @@
 
 package com.yourcompany.platforminteraction;
 
-import android.os.Bundle;
-import io.flutter.app.FlutterActivity;
+import androidx.annotation.NonNull;
+import io.flutter.embedding.android.FlutterActivity;
+import io.flutter.embedding.engine.FlutterEngine;
 import io.flutter.plugins.GeneratedPluginRegistrant;
-import io.flutter.view.FlutterView;
 
 public class MainActivity extends FlutterActivity {
   @Override
-  protected void onCreate(Bundle savedInstanceState) {
-      super.onCreate(savedInstanceState);
-      GeneratedPluginRegistrant.registerWith(this);
+  public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
+    GeneratedPluginRegistrant.registerWith(flutterEngine);
   }
 }
diff --git a/dev/integration_tests/release_smoke_test/android/app/src/main/AndroidManifest.xml b/dev/integration_tests/release_smoke_test/android/app/src/main/AndroidManifest.xml
index 6d6bc99..f93ecc4 100644
--- a/dev/integration_tests/release_smoke_test/android/app/src/main/AndroidManifest.xml
+++ b/dev/integration_tests/release_smoke_test/android/app/src/main/AndroidManifest.xml
@@ -33,5 +33,10 @@
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+    <!-- Don't delete the meta-data below.
+         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
     </application>
 </manifest>
diff --git a/dev/integration_tests/release_smoke_test/android/app/src/main/java/com/example/release_smoke_test/MainActivity.java b/dev/integration_tests/release_smoke_test/android/app/src/main/java/com/example/release_smoke_test/MainActivity.java
index 2d980d6..abd9bf8 100644
--- a/dev/integration_tests/release_smoke_test/android/app/src/main/java/com/example/release_smoke_test/MainActivity.java
+++ b/dev/integration_tests/release_smoke_test/android/app/src/main/java/com/example/release_smoke_test/MainActivity.java
@@ -4,14 +4,14 @@
 
 package com.example.release_smoke_test;
 
-import android.os.Bundle;
-import io.flutter.app.FlutterActivity;
+import androidx.annotation.NonNull;
+import io.flutter.embedding.android.FlutterActivity;
+import io.flutter.embedding.engine.FlutterEngine;
 import io.flutter.plugins.GeneratedPluginRegistrant;
 
 public class MainActivity extends FlutterActivity {
   @Override
-  protected void onCreate(Bundle savedInstanceState) {
-    super.onCreate(savedInstanceState);
-    GeneratedPluginRegistrant.registerWith(this);
+  public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
+    GeneratedPluginRegistrant.registerWith(flutterEngine);
   }
 }
diff --git a/dev/integration_tests/ui/android/app/src/main/AndroidManifest.xml b/dev/integration_tests/ui/android/app/src/main/AndroidManifest.xml
index de54305..897ab0c 100644
--- a/dev/integration_tests/ui/android/app/src/main/AndroidManifest.xml
+++ b/dev/integration_tests/ui/android/app/src/main/AndroidManifest.xml
@@ -28,5 +28,10 @@
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+    <!-- Don't delete the meta-data below.
+         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
     </application>
 </manifest>
diff --git a/dev/integration_tests/ui/android/app/src/main/java/com/yourcompany/integration_ui/MainActivity.java b/dev/integration_tests/ui/android/app/src/main/java/com/yourcompany/integration_ui/MainActivity.java
index 98f51d4..cab904f 100644
--- a/dev/integration_tests/ui/android/app/src/main/java/com/yourcompany/integration_ui/MainActivity.java
+++ b/dev/integration_tests/ui/android/app/src/main/java/com/yourcompany/integration_ui/MainActivity.java
@@ -4,14 +4,14 @@
 
 package com.yourcompany.integration_ui;
 
-import android.os.Bundle;
-import io.flutter.app.FlutterActivity;
+import androidx.annotation.NonNull;
+import io.flutter.embedding.android.FlutterActivity;
+import io.flutter.embedding.engine.FlutterEngine;
 import io.flutter.plugins.GeneratedPluginRegistrant;
 
 public class MainActivity extends FlutterActivity {
   @Override
-  protected void onCreate(Bundle savedInstanceState) {
-    super.onCreate(savedInstanceState);
-    GeneratedPluginRegistrant.registerWith(this);
+  public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
+    GeneratedPluginRegistrant.registerWith(flutterEngine);
   }
 }