Flight client error stack (#25560)

restore error message into stack for flight prod errors

Author: gnoff

packages/react-client/src/ReactFlightClient.js

@@ -646,7 +646,7 @@ export function resolveErrorProd(
       ' builds to avoid leaking sensitive details. A digest property is included on this error instance which' +
       ' may provide additional details about the nature of the error.',
   );
-  error.stack = '';
+  error.stack = 'Error: ' + error.message;
   (error: any).digest = digest;
   const errorWithDigest: ErrorWithDigest = (error: any);
   const chunks = response._chunks;

packages/react-client/src/__tests__/ReactFlight-test.js

@@ -57,6 +57,9 @@ describe('ReactFlight', () => {
               ' may provide additional details about the nature of the error.',
           );
           expect(this.state.error.digest).toContain(this.props.expectedMessage);
+          expect(this.state.error.stack).toBe(
+            'Error: ' + this.state.error.message,
+          );
         }
       }
       render() {