Auto merge of #16036 - chenpighead:text-size-adjust, r=upsuper

Stylo: Add support for text-size-adjust property

<!-- Please describe your changes on the following line: -->

Gecko supports -{moz,webkit}-text-size-adjust properties, but it only supports auto and none value.
Implement parsing/serialization for text-size-adjust property and its gecko glue.

---
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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 #16002 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/style/properties/gecko.mako.rs

@@ -2606,7 +2606,7 @@ fn static_assert() {
 
 <%self:impl_trait style_struct_name="InheritedText"
                   skip_longhands="text-align text-emphasis-style text-shadow line-height letter-spacing word-spacing
-                                  -webkit-text-stroke-width text-emphasis-position -moz-tab-size">
+                                  -webkit-text-stroke-width text-emphasis-position -moz-tab-size -moz-text-size-adjust">
 
     <% text_align_keyword = Keyword("text-align", "start end left right center justify -moz-center -moz-left " +
                                                   "-moz-right match-parent char") %>
@@ -2789,6 +2789,10 @@ fn static_assert() {
 
     <%call expr="impl_coord_copy('_moz_tab_size', 'mTabSize')"></%call>
 
+    <% text_size_adjust_keyword = Keyword("text-size-adjust", "auto none") %>
+
+    ${impl_keyword('_moz_text_size_adjust', 'mTextSizeAdjust', text_size_adjust_keyword, need_clone=False)}
+
 </%self:impl_trait>
 
 <%self:impl_trait style_struct_name="Text"

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

@@ -169,6 +169,13 @@ ${helpers.single_keyword("hyphens", "manual none auto",
                          products="gecko", animatable=False, extra_prefixes="moz",
                          spec="https://drafts.csswg.org/css-text/#propdef-hyphens")}
 
+// TODO: Support <percentage>
+${helpers.single_keyword("-moz-text-size-adjust", "auto none",
+                         gecko_constant_prefix="NS_STYLE_TEXT_SIZE_ADJUST",
+                         products="gecko", animatable=False,
+                         spec="https://drafts.csswg.org/css-size-adjust/#adjustment-control",
+                         alias="-webkit-text-size-adjust")}
+
 ${helpers.predefined_type("text-indent",
                           "LengthOrPercentage",
                           "computed::LengthOrPercentage::Length(Au(0))",