Reland "[heap] Fine-grained JSArrayBuffer tracking"

test/cctest/heap/heap-utils.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "test/cctest/heap/heap-utils.h"
 
 #include "src/factory.h"
 #include "src/heap/heap-inl.h"
 #include "src/heap/incremental-marking.h"
 #include "src/heap/mark-compact.h"
@@ skipping 123 matching lines @@
   }
   CHECK(marking->IsComplete());
 }
 
 void SimulateFullSpace(v8::internal::PagedSpace* space) {
   space->EmptyAllocationInfo();
   space->ResetFreeList();
   space->ClearStats();
 }
 
+void AbandonCurrentlyFreeMemory(PagedSpace* space) {
+  space->EmptyAllocationInfo();
+  PageIterator pit(space);
+  while (pit.has_next()) {
+    pit.next()->MarkNeverAllocateForTesting();
+  }
+}
+
+void GcAndSweep(Heap* heap, AllocationSpace space) {
+  heap->CollectGarbage(space);
+  if (heap->mark_compact_collector()->sweeping_in_progress()) {
+    heap->mark_compact_collector()->EnsureSweepingCompleted();
+  }
+}
+
 }  // namespace heap
 }  // namespace internal
 }  // namespace v8