Made the android platform channel benchmarks comparable to iOS (#83110)

dev/benchmarks/platform_channels_benchmarks/android/app/src/main/kotlin/com/example/platform_channels_benchmarks/MainActivity.kt

@@ -12,15 +12,24 @@ import io.flutter.plugin.common.StandardMessageCodec
 import java.nio.ByteBuffer
 
 class MainActivity: FlutterActivity() {
-
+    // We allow for the caching of a response in the binary channel case since
+    // the reply requires a direct buffer, but the input is not a direct buffer.
+    // We can't directly send the input back to the reply currently.
+    private var byteBufferCache : ByteBuffer? = null
     override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
+        val reset = BasicMessageChannel(flutterEngine.dartExecutor, "dev.flutter.echo.reset", StandardMessageCodec.INSTANCE)
+        reset.setMessageHandler { message, reply -> run {
+            byteBufferCache = null
+        } }
         val basicStandard = BasicMessageChannel(flutterEngine.dartExecutor, "dev.flutter.echo.basic.standard", StandardMessageCodec.INSTANCE)
         basicStandard.setMessageHandler { message, reply -> reply.reply(message) }
         val basicBinary = BasicMessageChannel(flutterEngine.dartExecutor, "dev.flutter.echo.basic.binary", BinaryCodec.INSTANCE)
         basicBinary.setMessageHandler { message, reply -> run {
-            val result = ByteBuffer.allocateDirect(message!!.capacity())
+            if (byteBufferCache == null) {
-            result.put(message)
+                byteBufferCache = ByteBuffer.allocateDirect(message!!.capacity())
-            reply.reply(result)
+                byteBufferCache!!.put(message)
+            }
+            reply.reply(byteBufferCache)
         } }
         super.configureFlutterEngine(flutterEngine)
     }

dev/benchmarks/platform_channels_benchmarks/ios/Runner/AppDelegate.swift

@@ -14,6 +14,11 @@ import UIKit
     GeneratedPluginRegistrant.register(with: self)
 
     let registrar = self.registrar(forPlugin: "Echo")!
+    let reset = FlutterBasicMessageChannel(
+      name: "dev.flutter.echo.reset", binaryMessenger: registrar.messenger())
+    reset.setMessageHandler { (input, reply) in
+      // noop
+    }
     let basicStandard = FlutterBasicMessageChannel(
       name: "dev.flutter.echo.basic.standard", binaryMessenger: registrar.messenger(),
       codec: FlutterStandardMessageCodec.sharedInstance())

dev/benchmarks/platform_channels_benchmarks/lib/main.dart

@@ -108,6 +108,10 @@ Future<void> _runTests() async {
     );
   }
 
+  const BasicMessageChannel<Object> resetChannel = BasicMessageChannel<Object>(
+    'dev.flutter.echo.reset',
+    StandardMessageCodec(),
+  );
   const BasicMessageChannel<Object> basicStandard = BasicMessageChannel<Object>(
     'dev.flutter.echo.basic.standard',
     StandardMessageCodec(),
@@ -129,6 +133,7 @@ Future<void> _runTests() async {
   const int numMessages = 2500;
 
   final BenchmarkResultPrinter printer = BenchmarkResultPrinter();
+  resetChannel.send(true);
   await _runBasicStandardSmall(basicStandard, 1); // Warmup.
   printer.addResult(
     description: 'BasicMessageChannel/StandardMessageCodec/Flutter->Host/Small',
@@ -136,6 +141,7 @@ Future<void> _runTests() async {
     unit: 'µs',
     name: 'platform_channel_basic_standard_2host_small',
   );
+  resetChannel.send(true);
   await _runBasicStandardLarge(basicStandard, largeBuffer, 1); // Warmup.
   printer.addResult(
     description: 'BasicMessageChannel/StandardMessageCodec/Flutter->Host/Large',
@@ -144,6 +150,7 @@ Future<void> _runTests() async {
     unit: 'µs',
     name: 'platform_channel_basic_standard_2host_large',
   );
+  resetChannel.send(true);
   await _runBasicBinary(basicBinary, largeBufferBytes, 1); // Warmup.
   printer.addResult(
     description: 'BasicMessageChannel/BinaryCodec/Flutter->Host/Large',
@@ -151,6 +158,7 @@ Future<void> _runTests() async {
     unit: 'µs',
     name: 'platform_channel_basic_binary_2host_large',
   );
+  resetChannel.send(true);
   await _runBasicBinary(basicBinary, oneMB, 1); // Warmup.
   printer.addResult(
     description: 'BasicMessageChannel/BinaryCodec/Flutter->Host/1MB',