Auto merge of #16285 - stshine:inline-block-margin, r=emilio

layout: Use the margin box of an inline block when computing the inline size

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When computing the inline size of an inline block in inline formating
context, use the margin box of the underling block.

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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12413 (github issue number if applicable).

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components/layout/fragment.rs

@@ -2380,10 +2380,7 @@ impl Fragment {
     pub fn update_late_computed_replaced_inline_size_if_necessary(&mut self) {
         if let SpecificFragmentInfo::InlineBlock(ref mut inline_block_info) = self.specific {
             let block_flow = FlowRef::deref_mut(&mut inline_block_info.flow_ref).as_block();
-            let margin = block_flow.fragment.style.logical_margin();
-            self.border_box.size.inline = block_flow.fragment.border_box.size.inline +
-                MaybeAuto::from_style(margin.inline_start, Au(0)).specified_or_zero() +
-                MaybeAuto::from_style(margin.inline_end, Au(0)).specified_or_zero()
+            self.border_box.size.inline = block_flow.fragment.margin_box_inline_size();
         }
     }