webcore: revoke a Worker's blob URLs when the worker exits - #35828

Bare `.rejects.toThrow()` passes on any rejection, so this line doesn't actually pin the revoked-URL behavior — REVIEW.md asks for a specific error class/code/message (never bare `toThrow()`). Consider asserting the actual error, e.g. ``.rejects.toThrow(TypeError)`` or matching `/Failed to resolve blob:/` (which is what `fetch` on a missing blob URL produces). Nit only — line 140's `resolveObjectURL(url)` → `undefined` already proves revocation.

nit: both new tests await `new Promise(resolve => worker.once("message", resolve))` without wiring `worker.once("error", reject)`. If a regression breaks Worker eval startup or `URL.createObjectURL` inside the worker, `message` never fires and the test hangs to the file timeout instead of failing fast with the actual error. Same shape at line 152. REVIEW.md: "Wire EVERY failure event (`error`, `close`, `abort`, process exit) to reject the awaited promise."