Auto merge of #23318 - asajeffrey:magicleap-debugmozjs, r=jdm

Fix magicleap debugmozjs

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These changes get magicleap servo to compile with `--debugmozjs`.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #23074 and fix #22069
- [X] These changes do not require tests because we're not building debugmozjs servo for magicleap

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python/servo/build_commands.py

@@ -212,11 +212,6 @@ class MachCommands(CommandBase):
             print("Please specify either --target or --android.")
             sys.exit(1)
 
-        # https://github.com/servo/servo/issues/22069
-        if debug_mozjs and magicleap:
-            print("Please specify either --debug-mozjs or --magicleap.")
-            sys.exit(1)
-
         if android:
             target = self.config["android"]["target"]
 
@@ -576,6 +571,7 @@ class MachCommands(CommandBase):
             env.setdefault("HARFBUZZ_SYS_NO_PKG_CONFIG", "1")
             env.setdefault("PKG_CONFIG_ALLOW_CROSS", "1")
             env.setdefault("CMAKE_TOOLCHAIN_FILE", path.join(ml_support, "toolchain.cmake"))
+            env.setdefault("_LIBCPP_INLINE_VISIBILITY", "__attribute__((__always_inline__))")
 
             # The Open SSL configuration
             env.setdefault("OPENSSL_DIR", path.join(target_path, target, "native", "openssl"))