Auto merge of #14895 - dowoncha:request-websocket, r=jdm

Added Websocket to RequestMode enum

Added Websocket to RequestMode enum
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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 #14785  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because matching the enum should have default control flow.

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components/script/dom/request.rs

@@ -826,6 +826,7 @@ impl Into<RequestMode> for NetTraitsRequestMode {
             NetTraitsRequestMode::SameOrigin => RequestMode::Same_origin,
             NetTraitsRequestMode::NoCors => RequestMode::No_cors,
             NetTraitsRequestMode::CorsMode => RequestMode::Cors,
+            NetTraitsRequestMode::WebSocket => unreachable!("Websocket request mode should never be exposed to JS"),
         }
     }
 }