[heap] Remove Heap::external_memory_concurrently_freed

The only user was ArrayBufferTracker which got removed already.

Bug: v8:10064
Change-Id: I97f8ed0727abec01b3b65ba965026f61fb9acb85
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2346406
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69354}

src/heap/heap-inl.h

@@ -91,16 +91,6 @@ void Heap::update_external_memory(int64_t delta) {
   }
 }
 
-void Heap::update_external_memory_concurrently_freed(uintptr_t freed) {
-  external_memory_concurrently_freed_ += freed;
-}
-
-void Heap::account_external_memory_concurrently_freed() {
-  update_external_memory(
-      -static_cast<int64_t>(external_memory_concurrently_freed_));
-  external_memory_concurrently_freed_ = 0;
-}
-
 RootsTable& Heap::roots_table() { return isolate()->roots_table(); }
 
 #define ROOT_ACCESSOR(Type, name, CamelName)                           \

src/heap/heap.h

@@ -668,8 +668,6 @@ class Heap {
 
   V8_INLINE int64_t external_memory();
   V8_INLINE void update_external_memory(int64_t delta);
-  V8_INLINE void update_external_memory_concurrently_freed(uintptr_t freed);
-  V8_INLINE void account_external_memory_concurrently_freed();
 
   V8_EXPORT_PRIVATE size_t YoungArrayBufferBytes();
   V8_EXPORT_PRIVATE size_t OldArrayBufferBytes();

src/heap/mark-compact.cc

@@ -894,8 +894,6 @@ void MarkCompactCollector::Prepare() {
     heap_->safepoint()->IterateLocalHeaps(
         [](LocalHeap* local_heap) { local_heap->FreeLinearAllocationArea(); });
   }
-
-  heap()->account_external_memory_concurrently_freed();
 }
 
 void MarkCompactCollector::FinishConcurrentMarking(
@@ -4495,8 +4493,6 @@ void MinorMarkCompactCollector::CollectGarbage() {
     heap()->new_lo_space()->FreeDeadObjects([](HeapObject) { return true; });
   }
 
-  heap()->account_external_memory_concurrently_freed();
-
   SweepArrayBufferExtensions();
 }