memory leak in proxy_on_platform_messsage.

[james-lawrence]

see documentation

func proxy_on_platform_message(message *C.FlutterPlatformMessage, userPointer unsafe.Pointer) C.bool {
	if message.message != nil {
		str := C.GoString(C.converter(message.message, message.message_size))

		FlutterPlatformMessage := PlatformMessage{}

		messageContent := Message{}
		json.Unmarshal([]byte(str), &messageContent)

		FlutterPlatformMessage.Message = messageContent
		FlutterPlatformMessage.Channel = C.GoString(message.channel)
		if message.response_handle == nil {
			fmt.Println("==================== NIL")
		}

		return C.bool(globalFlutterOpenGL.FPlatfromMessage(FlutterPlatformMessage, userPointer))
	}
	return C.bool(false)

}

if message.response_handle == nil

should be

FlutterPlatformMessage.ResponseHandle = (*platformMessageResponseHandle)(message.response_handle)

we would still need to handle the response later on but this moves the needle in the right direction.

[pchampio]

For the keyboard input we have to ignore this field.
The Doc says:

This field is ignored for messages being sent from the embedder to the framework

And since we are using FlutterEngineSendPlatformMessage (Can send multiple messages) and not FlutterEngineSendPlatformMessageResponse(Can send ONE message for One response), this is not a memory leak.