Auto merge of #10359 - bholley:style_struct_management, r=SimonSapin

Implement construction, destruction, and copying of gecko style structs

This requires some new machinery on the gecko side, which I'll get up in bugzilla shortly.

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1 files changed, 8 insertions, 4 deletions

diff --git a/components/style/properties.mako.rs b/components/style/properties.mako.rs
index ce285c4d71b..0b9dcd11217 100644
--- a/components/style/properties.mako.rs
+++ b/components/style/properties.mako.rs
@@ -6722,10 +6722,8 @@ pub type CascadePropertyFn<C /*: ComputedValues */> =
                      cacheable: &mut bool,
                      error_reporter: &mut Box<ParseErrorReporter + Send>);
 
-// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
-// properties.
-thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
-    let mut result: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = Vec::new();
+pub fn make_cascade_vec<C: ComputedValues>() -> Vec<Option<CascadePropertyFn<C>>> {
+    let mut result: Vec<Option<CascadePropertyFn<C>>> = Vec::new();
     % for style_struct in STYLE_STRUCTS:
         % for property in style_struct.longhands:
             let discriminant;
@@ -6741,6 +6739,12 @@ thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoCompute
         % endfor
     % endfor
     result
+}
+
+// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
+// properties.
+thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
+    make_cascade_vec::<ServoComputedValues>()
 });
 
 /// Performs the CSS cascade, computing new styles for an element from its parent style and