Auto merge of #16537 - KuoE0:add-inline-axis-and-block-axis-for-moz-box-orient, r=KuoE0

Add `inline-axis` and `block-axis` aliases for `-moz-box-orient`.

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This issue is reported at https://bugzilla.mozilla.org/show_bug.cgi?id=1355005.

spec: https://developer.mozilla.org/en-US/docs/Web/CSS/box-orient

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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 [Bug 1355005](https://bugzilla.mozilla.org/show_bug.cgi?id=1355005)

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- [X] These changes do not require tests in Gecko.

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components/style/properties/longhand/xul.mako.rs

@@ -31,6 +31,7 @@ ${helpers.predefined_type("-moz-box-flex", "Number", "0.0", "parse_non_negative"
 
 ${helpers.single_keyword("-moz-box-orient", "horizontal vertical",
                          products="gecko", gecko_ffi_name="mBoxOrient",
+                         extra_gecko_aliases="inline-axis=horizontal block-axis=vertical",
                          gecko_enum_prefix="StyleBoxOrient",
                          animation_type="none",
                          alias="-webkit-box-orient",