PartitionAlloc: Add missing UsesGigaCage.

Bug: 11297512
Change-Id: I9283feaa8578df3cfd749831e9d48c9151fe9c71
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2505986
Auto-Submit: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#822197}

base/allocator/partition_allocator/partition_bucket.cc

@@ -268,7 +268,7 @@ ALWAYS_INLINE void* PartitionBucket<thread_safe>::AllocNewSlotSpan(
   // Allocate from GigaCage, if enabled. However, the exception to this is when
   // tags aren't allowed, as CheckedPtr assumes that everything inside GigaCage
   // uses tags (specifically, inside the GigaCage's normal bucket pool).
-  if (root->allow_extras && features::IsPartitionAllocGigaCageEnabled()) {
+  if (root->UsesGigaCage()) {
     super_page = AddressPoolManager::GetInstance()->Alloc(
         GetNormalBucketPool(), requested_address, kSuperPageSize);
   } else {