Bug 313736

The spec's "reject the credential request with" algorithm (https://w3c-fedid.github.io/digital-credentials/#reject-the-credential-request) requires: "Queue a global task on the DOM manipulation task source given |promise|'s relevant global object to perform the following steps: - [cleanup abort signal/algorithm] - Reject |promise| with |error| - Set active promise to null - Set interaction state to idle" Similarly, the success path in "initiate the credential request" (step 3e.iii) also requires: "Queue a global task on the DOM manipulation task source given |document|'s relevant global object to perform the following steps: - [parse JSON, create DigitalCredential, resolve promise] - Set active promise to null - Set interaction state to idle" WebKit's dismissPickerAndSettle() does not queue a global task — it runs the rejection/resolution inside the dismissDigitalCredentialsPicker completion callback. Similarly, the success path in handleDigitalCredentialsPickerResult resolves synchronously. Both paths need to be restructured to queue a global task on the DOM manipulation task source. Note: Bug 311790 covers the specific case of the non-idle rejection in "prepare credential requests" step 2. This bug is broader — it covers the shared reject algorithm and the success path, which are used by all error and success code paths.