Provide baseline for new GC infrastructure.

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 0497ad5f6a3d0b12ff72fbf94c6c61f43f8dab4b..d782d6304784d7cffe37d8038a56c9d6fab684c0 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -226,6 +226,7 @@ int Heap::GcSafeSizeOfOldObject(HeapObject* object) {
 
 
 int Heap::GcSafeSizeOfOldObjectWithEncodedMap(HeapObject* object) {
+  ASSERT(!FLAG_new_gc);  // Should not be used in new GC.
   ASSERT(!Heap::InNewSpace(object));  // Code only works for old objects.
   ASSERT(MarkCompactCollector::are_map_pointers_encoded());
   uint32_t marker = Memory::uint32_at(object->address());
@@ -3984,9 +3985,14 @@ void Heap::Verify() {
 
   new_space_.Verify();
 
-  VerifyPointersAndDirtyRegionsVisitor dirty_regions_visitor;
-  old_pointer_space_->Verify(&dirty_regions_visitor);
-  map_space_->Verify(&dirty_regions_visitor);
+  if (!FLAG_new_gc) {
+    VerifyPointersAndDirtyRegionsVisitor dirty_regions_visitor;
+    old_pointer_space_->Verify(&dirty_regions_visitor);
+    map_space_->Verify(&dirty_regions_visitor);
+  } else {
+    old_pointer_space_->Verify(&visitor);
+    map_space_->Verify(&visitor);
+  }
 
   VerifyPointersUnderWatermark(old_pointer_space_,
                                &IteratePointersInDirtyRegion);
@@ -4207,6 +4213,11 @@ uint32_t Heap::IterateDirtyRegions(
     Address area_end,
     DirtyRegionCallback visit_dirty_region,
     ObjectSlotCallback copy_object_func) {
+  if (FLAG_new_gc) {
+    visit_dirty_region(area_start, area_end, copy_object_func);
+    return Page::kAllRegionsDirtyMarks;
+  }
+
   uint32_t newmarks = 0;
   uint32_t mask = 1;