Reland "Only use FreeSpace objects in the free list"

src/allocation-tracker.cc

 // Copyright 2013 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 "src/v8.h"
 
 #include "src/allocation-tracker.h"
 #include "src/frames-inl.h"
 #include "src/heap-snapshot-generator.h"
 
@@ skipping 209 matching lines @@
   }
 }
 
 
 void AllocationTracker::AllocationEvent(Address addr, int size) {
   DisallowHeapAllocation no_allocation;
   Heap* heap = ids_->heap();
 
   // Mark the new block as FreeSpace to make sure the heap is iterable
   // while we are capturing stack trace.
-  FreeListNode::FromAddress(addr)->set_size(heap, size);
-  DCHECK_EQ(HeapObject::FromAddress(addr)->Size(), size);
-  DCHECK(FreeListNode::IsFreeListNode(HeapObject::FromAddress(addr)));
+  heap->CreateFillerObjectAt(addr, size);
 
   Isolate* isolate = heap->isolate();
   int length = 0;
   StackTraceFrameIterator it(isolate);
   while (!it.done() && length < kMaxAllocationTraceLength) {
     JavaScriptFrame* frame = it.frame();
     SharedFunctionInfo* shared = frame->function()->shared();
     SnapshotObjectId id = ids_->FindOrAddEntry(
         shared->address(), shared->Size(), false);
     allocation_trace_buffer_[length++] = AddFunctionInfo(shared, id);
@@ skipping 90 matching lines @@
 void AllocationTracker::UnresolvedLocation::HandleWeakScript(
     const v8::WeakCallbackData<v8::Value, void>& data) {
   UnresolvedLocation* loc =
       reinterpret_cast<UnresolvedLocation*>(data.GetParameter());
   GlobalHandles::Destroy(reinterpret_cast<Object**>(loc->script_.location()));
   loc->script_ = Handle<Script>::null();
 }
 
 
 } }  // namespace v8::internal