Chrome buffers text/plain stream (mistakenly?)

I sent a issue for Chrome; Chrome buffers text/plain stream and doesn't display it immediately.

• Demo: http://polar-badlands-7200.herokuapp.com/
• Source: https://github.com/kentaro/chrome-and-safari-streaming-problem

For details, please refer to the page above. I don't know it's correct behavior or not. But it seemed to start from some recent time.