Auto merge of #24339 - servo:sharing-cache-size, r=emilio

Remove obsolete logic for LRUCache size

The LRUCache implementation has been replaced, and no longer requires a backing store larger than its capacity.

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1 files changed, 3 insertions, 6 deletions

diff --git a/components/style/sharing/mod.rs b/components/style/sharing/mod.rs
index 38fd6283436..9b8c1275e4b 100644
--- a/components/style/sharing/mod.rs
+++ b/components/style/sharing/mod.rs
@@ -90,17 +90,14 @@ use uluru::{Entry, LRUCache};
 mod checks;
 
 /// The amount of nodes that the style sharing candidate cache should hold at
-/// most.  We'd somewhat like 32, but ArrayDeque only implements certain backing
-/// store sizes.  A cache size of 32 would mean a backing store of 33, but
-/// that's not an implemented size: we can do 32 or 40.
+/// most.
 ///
 /// The cache size was chosen by measuring style sharing and resulting
 /// performance on a few pages; sizes up to about 32 were giving good sharing
 /// improvements (e.g. 3x fewer styles having to be resolved than at size 8) and
 /// slight performance improvements.  Sizes larger than 32 haven't really been
 /// tested.
-pub const SHARING_CACHE_SIZE: usize = 31;
-const SHARING_CACHE_BACKING_STORE_SIZE: usize = SHARING_CACHE_SIZE + 1;
+pub const SHARING_CACHE_SIZE: usize = 32;
 
 /// Opaque pointer type to compare ComputedValues identities.
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -426,7 +423,7 @@ impl<E: TElement> StyleSharingTarget<E> {
 }
 
 struct SharingCacheBase<Candidate> {
-    entries: LRUCache<[Entry<Candidate>; SHARING_CACHE_BACKING_STORE_SIZE]>,
+    entries: LRUCache<[Entry<Candidate>; SHARING_CACHE_SIZE]>,
 }
 
 impl<Candidate> Default for SharingCacheBase<Candidate> {