Auto merge of #14848 - bzbarsky:initial-styles, r=bholley

Stop using global initial styles for stylo; the initial styles need to be per-document

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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 https://bugzilla.mozilla.org/show_bug.cgi?id=1298588

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests on the servo side because behavior is unchanged.  Gecko-side tests probably exist.

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1 files changed, 3 insertions, 1 deletions

diff --git a/components/script_layout_interface/wrapper_traits.rs b/components/script_layout_interface/wrapper_traits.rs
index 77414fa48d5..0103b185096 100644
--- a/components/script_layout_interface/wrapper_traits.rs
+++ b/components/script_layout_interface/wrapper_traits.rs
@@ -391,6 +391,7 @@ pub trait ThreadSafeLayoutElement: Clone + Copy + Sized + Debug +
                                 context.stylist.precomputed_values_for_pseudo(
                                     &style_pseudo,
                                     Some(&data.styles().primary.values),
+                                    &context.default_computed_values,
                                     false);
                             data.styles_mut().pseudos
                                 .insert(style_pseudo.clone(), new_style.unwrap());
@@ -407,7 +408,8 @@ pub trait ThreadSafeLayoutElement: Clone + Copy + Sized + Debug +
                                        .lazily_compute_pseudo_element_style(
                                            self,
                                            &style_pseudo,
-                                           &data.styles().primary.values);
+                                           &data.styles().primary.values,
+                                           &context.default_computed_values);
                             data.styles_mut().pseudos
                                 .insert(style_pseudo.clone(), new_style.unwrap());
                         }