servo: Merge #11549 - Generate debug and release Gecko bindings (from heycam:release-bindings); r=heycam

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This makes `generate_style_structs.py` generate bindings for both `DEBUG` and non-`DEBUG` Gecko configurations.  The corresponding generated bindings are used in geckolib based on `cfg(debug-assertions)`.

I regenerated bindings on top of Gecko master plus https://bugzilla.mozilla.org/show_bug.cgi?id=1277154 (landing soon), which tripped up the bindgen due to bitfield layout issues.

r? @emilio

---
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- [ ] `./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 they are geckolib only

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Source-Repo: https://github.com/servo/servo
Source-Revision: 71db2705edbf2381849af0e2edf7743c286881ec

servo/python/tidy/servo_tidy/tidy.py

@@ -34,7 +34,8 @@ file_patterns_to_ignore = [
 ignored_files = [
     # Generated and upstream code combined with our own. Could use cleanup
     os.path.join(".", "ports", "geckolib", "gecko_bindings", "bindings.rs"),
-    os.path.join(".", "ports", "geckolib", "gecko_bindings", "structs.rs"),
+    os.path.join(".", "ports", "geckolib", "gecko_bindings", "structs_debug.rs"),
+    os.path.join(".", "ports", "geckolib", "gecko_bindings", "structs_release.rs"),
     os.path.join(".", "ports", "geckolib", "string_cache", "atom_macro.rs"),
     os.path.join(".", "resources", "hsts_preload.json"),
     os.path.join(".", "tests", "wpt", "metadata", "MANIFEST.json"),