Track JS allocations as they arrive with no affection on performance when tracking is switched off

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 23b7c89c4eace42a55d398bdf6ee9e68dbeab15d..dfabe279eeb6cf3e4839a1749d9142c7970b6ccd 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -2100,7 +2100,8 @@ class ScavengingVisitor : public StaticVisitorBase {
     if (logging_and_profiling_mode == LOGGING_AND_PROFILING_ENABLED) {
       // Update NewSpace stats if necessary.
       RecordCopiedObject(heap, target);
-      HEAP_PROFILE(heap, ObjectMoveEvent(source->address(), target->address()));
+      HEAP_PROFILE(heap,
+                   ObjectMoveEvent(source->address(), target->address(), size));
       Isolate* isolate = heap->isolate();
       if (isolate->logger()->is_logging_code_events() ||
           isolate->cpu_profiler()->is_profiling()) {
@@ -5074,6 +5075,14 @@ MaybeObject* Heap::CopyJSObjectWithAllocationSite(
     alloc_memento->set_map_no_write_barrier(allocation_memento_map());
     ASSERT(site->map() == allocation_site_map());
     alloc_memento->set_allocation_site(site, SKIP_WRITE_BARRIER);
+
+    HeapProfiler* profiler = isolate()->heap_profiler();
+    if (profiler->is_tracking_allocations()) {
+      profiler->UpdateObjectSizeEvent(HeapObject::cast(clone)->address(),
+                               object_size);
+      profiler->NewObjectEvent(alloc_memento->address(),
+                               adjusted_object_size - object_size);
+    }
   }
 
   SLOW_ASSERT(