9 files declare their use of RejectedPromise in Zircon Profile 8

CurlFactory.php in vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php

EachPromiseTest.php in vendor/guzzlehttp/promises/tests/EachPromiseTest.php

functionsTest.php in vendor/guzzlehttp/promises/tests/functionsTest.php

Middleware.php in vendor/guzzlehttp/guzzle/src/Middleware.php

MockHandler.php in vendor/guzzlehttp/guzzle/src/Handler/MockHandler.php

PromiseTest.php in vendor/guzzlehttp/promises/tests/PromiseTest.php

RejectedPromiseTest.php in vendor/guzzlehttp/promises/tests/RejectedPromiseTest.php

RetryMiddleware.php in vendor/guzzlehttp/guzzle/src/RetryMiddleware.php

StreamHandler.php in vendor/guzzlehttp/guzzle/src/Handler/StreamHandler.php