Summary:
The code to display HMR errors on the client was reading the `description` field from Metro payloads. Metro does not include `description` in the body of its error payloads -- only in its `body.errors[]` items. This commit changes RN's HMR code to show `body.message` (set consistently with https://github.com/facebook/metro/pull/124) instead of the non-existent `body.description`.
Open a test RN app, enable HMR, and then introduce a syntax error in an app source file. See that the redbox provides information about the syntax error instead of just saying "TransformError undefined".
- https://github.com/facebook/metro/pull/124
[GENERAL][ENHANCEMENT][HMR] - Fix display of syntax error messages when HMR is enabled
Closes https://github.com/facebook/react-native/pull/17619
Differential Revision: D6726516
Pulled By: mjesun
fbshipit-source-id: b1d1008d6f1aa8f88ff8a2aa1374724a305c773b