Auto merge of #24332 - saschanaz:mixin, r=jdm

Migrate to IDL mixin syntax

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- [x] These changes fix #22539

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/dom/webidls/Fetch.webidl b/components/script/dom/webidls/Fetch.webidl
index ad0907d7436..abedcf620ea 100644
--- a/components/script/dom/webidls/Fetch.webidl
+++ b/components/script/dom/webidls/Fetch.webidl
@@ -6,6 +6,6 @@
 
 [Exposed=(Window,Worker)]
 
-partial interface WindowOrWorkerGlobalScope {
+partial interface mixin WindowOrWorkerGlobalScope {
   [NewObject] Promise<Response> fetch(RequestInfo input, optional RequestInit init = {});
 };