Auto merge of #13419 - Coder206:swPromise, r=jdm

ServiceWorkerContainer::Promise

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13409  (github issue number if applicable).

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- [ ] There are tests for these changes

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/dom/webidls/ServiceWorkerContainer.webidl b/components/script/dom/webidls/ServiceWorkerContainer.webidl
index 45fb25063ff..6d183619af8 100644
--- a/components/script/dom/webidls/ServiceWorkerContainer.webidl
+++ b/components/script/dom/webidls/ServiceWorkerContainer.webidl
@@ -8,7 +8,7 @@ interface ServiceWorkerContainer : EventTarget {
   [Unforgeable] readonly attribute ServiceWorker? controller;
   //[SameObject] readonly attribute Promise<ServiceWorkerRegistration> ready;
 
-  [NewObject, Throws] ServiceWorkerRegistration register(USVString scriptURL, optional RegistrationOptions options);
+  [NewObject] Promise<ServiceWorkerRegistration> register(USVString scriptURL, optional RegistrationOptions options);
 
   //[NewObject] /*Promise<any>*/ any getRegistration(optional USVString clientURL = "");
   //[NewObject] /* Promise */<sequence<ServiceWorkerRegistration>> getRegistrations();