From 30fc50144a7702dba56adb6329d36fce1db6e682 Mon Sep 17 00:00:00 2001
From: Francisco Magdaleno <franciscojma86@gmail.com>
Date: Wed, 4 Sep 2019 10:24:04 -0700
Subject: [PATCH 1/3] Add missing InvokeMethod with a reply for glfw

---
 .../client_wrapper/include/flutter/method_channel.h   | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h b/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
index e1f164076aebb..19a773ca71ebf 100644
--- a/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
+++ b/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
@@ -51,8 +51,15 @@ class MethodChannel {
     messenger_->Send(name_, message->data(), message->size());
   }
 
-  // TODO: Add support for a version of InvokeMethod expecting a reply once
-  // https://github.com/flutter/flutter/issues/18852 is fixed.
+  // Sends a message to the Flutter engine on this channel expecting a reply.
+  void InvokeMethod(const std::string& method,
+                    std::unique_ptr<T> arguments,
+                    flutter::BinaryReply reply) {
+    MethodCall<T> method_call(method, std::move(arguments));
+    std::unique_ptr<std::vector<uint8_t>> message =
+        codec_->EncodeMethodCall(method_call);
+    messenger_->Send(name_, message->data(), message->size(), reply);
+  }
 
   // Registers a handler that should be called any time a method call is
   // received on this channel.

From baa15d71a7687cb7bccfcfa70691f09698e6ca8a Mon Sep 17 00:00:00 2001
From: Francisco Magdaleno Arceo <franciscojma@google.com>
Date: Wed, 4 Sep 2019 11:05:55 -0700
Subject: [PATCH 2/3] Add to macos

---
 .../darwin/common/framework/Headers/FlutterChannels.h       | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/shell/platform/darwin/common/framework/Headers/FlutterChannels.h b/shell/platform/darwin/common/framework/Headers/FlutterChannels.h
index 83c9e989762e4..b0a81e9e7de25 100644
--- a/shell/platform/darwin/common/framework/Headers/FlutterChannels.h
+++ b/shell/platform/darwin/common/framework/Headers/FlutterChannels.h
@@ -234,11 +234,7 @@ FLUTTER_EXPORT
  */
 - (void)invokeMethod:(NSString*)method
            arguments:(id _Nullable)arguments
-              result:(FlutterResult _Nullable)callback
-    // TODO: Add macOS support for replies once
-    // https://github.com/flutter/flutter/issues/18852 is fixed.
-    API_UNAVAILABLE(macos);
-
+              result:(FlutterResult _Nullable)callback;
 /**
  * Registers a handler for method calls from the Flutter side.
  *

From afe34a4bdbb681634aa9c3b97870f5425bfb83cb Mon Sep 17 00:00:00 2001
From: Francisco Magdaleno <franciscojma86@gmail.com>
Date: Wed, 4 Sep 2019 13:59:21 -0700
Subject: [PATCH 3/3] Refactor call

---
 .../cpp/client_wrapper/include/flutter/method_channel.h       | 2 +-
 shell/platform/common/cpp/client_wrapper/plugin_registrar.cc  | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h b/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
index 19a773ca71ebf..4baa083cca117 100644
--- a/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
+++ b/shell/platform/common/cpp/client_wrapper/include/flutter/method_channel.h
@@ -48,7 +48,7 @@ class MethodChannel {
     MethodCall<T> method_call(method, std::move(arguments));
     std::unique_ptr<std::vector<uint8_t>> message =
         codec_->EncodeMethodCall(method_call);
-    messenger_->Send(name_, message->data(), message->size());
+    messenger_->Send(name_, message->data(), message->size(), nullptr);
   }
 
   // Sends a message to the Flutter engine on this channel expecting a reply.
diff --git a/shell/platform/common/cpp/client_wrapper/plugin_registrar.cc b/shell/platform/common/cpp/client_wrapper/plugin_registrar.cc
index cf28181ed4410..7ca7c3de73b1c 100644
--- a/shell/platform/common/cpp/client_wrapper/plugin_registrar.cc
+++ b/shell/platform/common/cpp/client_wrapper/plugin_registrar.cc
@@ -98,8 +98,8 @@ void BinaryMessengerImpl::Send(const std::string& channel,
                                const size_t message_size,
                                BinaryReply reply) const {
   if (reply == nullptr) {
-    std::cerr << "Calling BinaryMessengerImpl::Send expecting a reply, but the "
-                 "callback is null.\n";
+    FlutterDesktopMessengerSend(messenger_, channel.c_str(), message,
+                                message_size);
     return;
   }
   struct Captures {