Auto merge of #18428 - emilio:find-push, r=nox

style: remove selector_map::find_push.

It has a single caller and is overly generic, which is going to make harder to
add fallible allocations to it.

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components/style/selector_map.rs

@@ -299,7 +299,10 @@ impl<T: SelectorMapEntry> SelectorMap<T> {
                 // rulehash lookup may produce superfluous selectors, but the
                 // subsequent selector matching work will filter them out.
                 if name != lower_name {
-                    find_push(&mut self.local_name_hash, lower_name.clone(), entry.clone());
+                    self.local_name_hash
+                        .entry(lower_name.clone())
+                        .or_insert_with(SmallVec::new)
+                        .push(entry.clone());
                 }
                 self.local_name_hash
                     .entry(name.clone())
@@ -485,15 +488,6 @@ fn find_bucket<'a>(mut iter: SelectorIter<'a, SelectorImpl>) -> Bucket<'a> {
     return current_bucket
 }
 
-#[inline]
-fn find_push<Str: Eq + Hash, V, VL>(map: &mut PrecomputedHashMap<Str, VL>,
-                                    key: Str,
-                                    value: V)
-    where VL: VecLike<V> + Default
-{
-    map.entry(key).or_insert_with(VL::default).push(value)
-}
-
 /// Wrapper for PrecomputedHashMap that does ASCII-case-insensitive lookup in quirks mode.
 #[derive(Debug)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]