Fix abstract_method_smoke_test flakiness (#42454)

The flake appears to be coming from the Google Maps plugin. This test
just needs a platform view plugin without the interface method
implemented in general, not Maps specifically. Update it here to avoid
the issue in Maps until that's fixed.

Create a very simple platform view implementation that exercises this
potential bug in order to create a minimal test case with less risk of
causing second order issues like depending on any kind of full package
would cause.

dev/integration_tests/abstract_method_smoke_test/android/app/src/main/AndroidManifest.xml

 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.example.abstract_method_smoke_test">
-    <!-- TODO(https://github.com/flutter/flutter/issues/42349): Remove this permission once this issue is fixed. -->
-    <uses-permission android:name="android.permission.WAKE_LOCK"/>
     <!-- io.flutter.app.FlutterApplication is an android.app.Application that
          calls FlutterMain.startInitialization(this); in its onCreate method.
          In most cases you can leave this as-is, but you if you want to provide
@@ -10,9 +8,6 @@
     <application
         android:name="io.flutter.app.FlutterApplication"
         android:label="abstract_method_smoke_test">
-        <meta-data
-            android:name="com.google.android.geo.API_KEY"
-            android:value="YOUR KEY HERE"/>
         <activity
             android:name=".MainActivity"
             android:launchMode="singleTop"

dev/integration_tests/abstract_method_smoke_test/android/app/src/main/kotlin/com/example/abstract_method_smoke_test/MainActivity.kt

 package com.example.abstract_method_smoke_test
 
 import android.content.Context
+import android.graphics.Color
 import android.os.Bundle
+import android.view.View
 import android.view.inputmethod.InputMethodManager
 import io.flutter.app.FlutterActivity
-import io.flutter.plugin.common.MethodChannel;
-import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
+import io.flutter.plugin.common.MethodChannel
+import io.flutter.plugin.common.StandardMessageCodec
+import io.flutter.plugin.platform.PlatformView
+import io.flutter.plugin.platform.PlatformViewFactory
 import io.flutter.plugins.GeneratedPluginRegistrant
 
-class MainActivity: FlutterActivity() {
+class MainActivity : FlutterActivity() {
+    class SimplePlatformView(context: Context) : PlatformView {
+        private val view: View = View(context)
+
+        init {
+            view.setBackgroundColor(Color.CYAN)
+        }
+
+        override fun dispose() {}
+
+        override fun getView(): View {
+            return view
+        }
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         GeneratedPluginRegistrant.registerWith(this)
 
+        registrarFor("com.example.abstract_method_smoke_test")
+                .platformViewRegistry()
+                .registerViewFactory("simple", object : PlatformViewFactory(StandardMessageCodec.INSTANCE) {
+                    override fun create(context: Context?, viewId: Int, args: Any?): PlatformView {
+                        return SimplePlatformView(this@MainActivity)
+                    }
+                })
+
         // Triggers the Android keyboard, which causes the resize of the Flutter view.
         // We need to wait for the app to complete.
-    MethodChannel(getFlutterView(), "com.example.abstract_method_smoke_test")
-        .setMethodCallHandler({ call, result ->
+        MethodChannel(flutterView, "com.example.abstract_method_smoke_test")
+                .setMethodCallHandler { _, result ->
                     toggleInput()
                     result.success(null)
-        })
+                }
     }
 
     override fun onPause() {
@@ -28,7 +54,7 @@ class MainActivity: FlutterActivity() {
         super.onPause()
     }
 
-  fun toggleInput() {
+    private fun toggleInput() {
         val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
         imm.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0)
     }

dev/integration_tests/abstract_method_smoke_test/lib/main.dart

 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
-import 'package:google_maps_flutter/google_maps_flutter.dart';
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
@@ -54,11 +53,7 @@ class SecondPage extends StatelessWidget {
       body: Column(
         children: const <Widget>[
           Expanded(
-            child: GoogleMap(
-              initialCameraPosition: CameraPosition(
-                target: LatLng(0, 0)
-              ),
-            ),
+            child: AndroidView(viewType: 'simple')
           ),
         ],
       ),

dev/integration_tests/abstract_method_smoke_test/pubspec.yaml

@@ -9,39 +9,13 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
-  google_maps_flutter: 0.5.21+7
 
   collection: 1.14.11 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   meta: 1.1.7 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   typed_data: 1.1.6 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   vector_math: 2.0.8 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
 
-dev_dependencies:
-  flutter_test:
-    sdk: flutter
-
-  archive: 2.0.10 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  args: 1.5.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  async: 2.3.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  boolean_selector: 1.0.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  charcode: 1.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  convert: 2.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  crypto: 2.1.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  image: 2.1.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  matcher: 0.12.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  path: 1.6.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  pedantic: 1.8.0+1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  petitparser: 2.4.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  quiver: 2.0.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  source_span: 1.5.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  stack_trace: 1.9.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  stream_channel: 2.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  string_scanner: 1.0.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  term_glyph: 1.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  test_api: 0.2.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-  xml: 3.5.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
-
 flutter:
   uses-material-design: true
 
-# PUBSPEC CHECKSUM: 2334
+# PUBSPEC CHECKSUM: 1d3d