LibWeb: Enable EXPLICIT_SYMBOL_EXPORT

Author: https://github.com/ayeteadoe
Commit: 3df8e00d91
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5229
Reviewed-by: https://github.com/ADKaster ✅

Libraries/LibWeb/Streams/UnderlyingSink.h

@@ -8,12 +8,13 @@
 
 #include <AK/Forward.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Streams {
 
 // https://streams.spec.whatwg.org/#dictdef-underlyingsink
-struct UnderlyingSink {
+struct WEB_API UnderlyingSink {
     GC::Root<WebIDL::CallbackType> start;
     GC::Root<WebIDL::CallbackType> write;
     GC::Root<WebIDL::CallbackType> close;