0.54's fetch doesn't bring us html .text()

[goodhyun]

Environment

Environment:
OS: macOS High Sierra 10.13.3
Node: 6.11.4
Yarn: Not Found
npm: 3.10.10
Watchman: 4.7.0
Xcode: Xcode 9.2 Build version 9C40b
Android Studio: 3.0 AI-171.4443003

Packages: (wanted => installed)
react: ^16.3.0-alpha.1 => 16.3.0-alpha.1
react-native: ^0.54.4 => 0.54.4

Steps to Reproduce

let res = await fetch("some.domain/index.html")
let text = await res.text()  

in this case, if it's not json but a plain html fetch, those text will be undefined.
In res, there is no _bodyText, it only has _bodyInit and _bodyBlob, which is understandable considering 0.54's change around fetch/Blob, but fetch's .text() doesn't seem to be working like previous versions.

Not sure whether this is related to #18547 or #18500

Expected Behavior

text should be populated with the HTML text.

Actual Behavior

undefined

0.53.3 is working like expected.

[Minishlink]

Had this issue today on iOS only: root cause was that the encoding was wrong on the file. Android parsed it without problem but iOS not. Check your file's encoding ;)

[stale]

Hey there, it looks like there has been no activity on this issue recently. Has the issue been fixed, or does it still require the community's attention? This issue may be closed if no further activity occurs. You may also label this issue as "For Discussion" or "Good first issue" and I will leave it open. Thank you for your contributions.

[stale]

Closing this issue after a prolonged period of inactivity. If this issue is still present in the latest release, please feel free to create a new issue with up-to-date information.