UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.62 Safari/537.36

Steps to reproduce the problem:
1. Create a Response with a ReadableStream that rejects:

  const response = new Response(new ReadableStream({                                        
    pull: (controller) => Promise.reject(Error('some reason'))                            
  }));  

2. Call Response.text() to extract the text:

  const text = await response.text()

   or

  response.text().then(
    (text) => { ... },
    (err) => { ... });

What is the expected behavior?
I expect the error to be "Error: some reason".

What went wrong?
All we get is the generic "TypeError: Failed to fetch"

Did this work before? N/A 

Chrome version: 62.0.3202.62  Channel: stable
OS Version: 4.4.0-97-generic
Flash Version: