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, 6 insertions, 0 deletions

diff --git a/components/layout_thread/lib.rs b/components/layout_thread/lib.rs
index 78a1295c1b5..4d25350835b 100644
--- a/components/layout_thread/lib.rs
+++ b/components/layout_thread/lib.rs
@@ -118,6 +118,7 @@ use style::error_reporting::{ParseErrorReporter, StdoutErrorReporter};
 use style::logical_geometry::LogicalPoint;
 use style::media_queries::{Device, MediaType};
 use style::parser::ParserContextExtraData;
+use style::properties::ComputedValues;
 use style::servo::restyle_damage::{REFLOW, REFLOW_OUT_OF_FLOW, REPAINT, REPOSITION, STORE_OVERFLOW};
 use style::stylesheets::{Origin, Stylesheet, UserAgentStylesheets};
 use style::stylist::Stylist;
@@ -527,6 +528,11 @@ impl LayoutThread {
                 local_context_creation_data: Mutex::new(thread_local_style_context_creation_data),
                 timer: self.timer.clone(),
                 quirks_mode: self.quirks_mode.unwrap(),
+                // FIXME(bz): This isn't really right, but it's no more wrong
+                // than what we used to do.  See
+                // https://github.com/servo/servo/issues/14773 for fixing it
+                // properly.
+                default_computed_values: Arc::new(ComputedValues::initial_values().clone()),
             },
             image_cache_thread: Mutex::new(self.image_cache_thread.clone()),
             image_cache_sender: Mutex::new(self.image_cache_sender.clone()),