Auto merge of #12940 - upsuper:binding-list, r=bholley

Include ServoBindingList.h for binding generating

<!-- Please describe your changes on the following line: -->
See [bug 1296594](https://bugzilla.mozilla.org/show_bug.cgi?id=1296594)

r? @bholley

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

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because binding code change

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This is bug 1296594 on Gecko side.

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ports/geckolib/binding_tools/regen.py

@@ -118,6 +118,7 @@ COMPILATION_TARGETS = {
             "-ignore-methods",
         ],
         "match_headers": [
+            "ServoBindingList.h",
             "ServoBindings.h",
             "nsStyleStructList.h",
         ],