Auto merge of #18460 - julian-seward1:master, r=emilio

Bug 1398593 - stylo: mitigate performance impact of fallible allocati…

…on on stylist rebuilds.  r=emilio.

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- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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components/fallible/lib.rs

@@ -27,7 +27,7 @@ pub trait FallibleVec<T> {
 // Vec
 
 impl<T> FallibleVec<T> for Vec<T> {
-    #[inline]
+    #[inline(always)]
     fn try_push(&mut self, val: T) -> Result<(), FailedAllocationError> {
         #[cfg(feature = "known_system_malloc")]
         {
@@ -92,7 +92,7 @@ fn try_double_vec<T>(vec: &mut Vec<T>) -> Result<(), FailedAllocationError> {
 // SmallVec
 
 impl<T: Array> FallibleVec<T::Item> for SmallVec<T> {
-    #[inline]
+    #[inline(always)]
     fn try_push(&mut self, val: T::Item) -> Result<(), FailedAllocationError> {
         #[cfg(feature = "known_system_malloc")]
         {

components/hashglobe/src/hash_map.rs

@@ -1002,6 +1002,7 @@ impl<K, V, S> HashMap<K, V, S>
         self.try_entry(key).unwrap()
     }
 
+    #[inline(always)]
     pub fn try_entry(&mut self, key: K) -> Result<Entry<K, V>, FailedAllocationError> {
         // Gotta resize now.
         self.try_reserve(1)?;