Allow to disable console output in dev tools

## Use case

My application uses plenty of logging during development. These are not just `print` statements but output from `logger` package. It's not unusual at some point that there will be 100s of lines printed to STDOUT, for example when my Flutter application is making network requests (I print out serialized responses).

Of course most of this is disabled for production builds. However when debugging my application this output causes the dev tools to freeze as it's trying to catch up and print everything to the console below.

## Proposal

I think ideal solution would be to improve performance of the web application (devtools). But I guess that might be tricky so at least allow me to:

1. Surpress messages to console completely (I already have output in my terminal where `flutter run` process is launched).
2. Allow me to close console pane completely and ignore any messages.

未指定文件或测试。首先定位 DevTools 控制台窗格，并跟踪应用程序日志消息如何到达该窗格。完成的标准是，用户可以抑制控制台消息或关闭窗格，从而忽略输出，同时不会导致 DevTools UI 卡死。

由索引模型根据 Issue 内容生成。