[cleanup] Remove unused LocalArrayBufferTracker::space

Bug: v8:9183
Change-Id: I583915848435b6ad3f42c320b72b7bb1a4eb2444
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1640207Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
Cr-Commit-Position: refs/heads/master@{#61967}

src/heap/array-buffer-tracker-inl.h

@@ -57,8 +57,6 @@ void ArrayBufferTracker::Unregister(Heap* heap, JSArrayBuffer buffer) {
   heap->update_external_memory(-static_cast<intptr_t>(length));
 }
 
-Space* LocalArrayBufferTracker::space() { return page_->owner(); }
-
 template <typename Callback>
 void LocalArrayBufferTracker::Free(Callback should_free) {
   size_t freed_memory = 0;

src/heap/array-buffer-tracker.h

@@ -117,8 +117,6 @@ class LocalArrayBufferTracker {
   // logic for updating external memory counters.
   inline void AddInternal(JSArrayBuffer buffer, size_t length);
 
-  inline Space* space();
-
   Page* page_;
   // The set contains raw heap pointers which are removed by the GC upon
   // processing the tracker through its owning page.