Auto merge of #13784 - TooManyBees:13363-check-script-enabled, r=Ms2ger

Issue 13363 - Step 1.2 of compiling event handler

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Adds the conditional to test that scripting is enabled in `EventTarget#get_compiled_event_handler`, and return `None` early if not.

Adds tests for "scripting enabled" and "scripting disabled" cases.

---
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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 #13363 (github issue number if applicable).

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- [x] There are tests for these changes

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components/script/dom/eventtarget.rs

@@ -373,7 +373,10 @@ impl EventTarget {
             None => self.downcast::<Window>().unwrap().Document(),
         };
 
-        // TODO step 1.2 (browsing context/scripting enabled)
+        // Step 1.2
+        if !document.is_scripting_enabled() {
+            return None;
+        }
 
         // Step 1.3
         let body: Vec<u16> = handler.source.encode_utf16().collect();