Implement a heap profiler for the Dart managed heap.

runtime/vm/pages.h

Index: runtime/vm/pages.h
diff --git a/runtime/vm/pages.h b/runtime/vm/pages.h
index 3dccc650ce434673d559c6295b50e7e2bf7c25aa..1da2a545f9475619561a3a01e630972c015eebc6 100644
--- a/runtime/vm/pages.h
+++ b/runtime/vm/pages.h
@@ -52,6 +52,7 @@ class HeapPage {
     return result;
   }
 
+  void VisitObjects(ObjectVisitor* visitor) const;
   void VisitObjectPointers(ObjectPointerVisitor* visitor) const;
 
   RawObject* FindObject(FindObjectVisitor* visitor) const;
@@ -98,6 +99,7 @@ class PageSpace {
     return size <= kAllocatablePageSize;
   }
 
+  void VisitObjects(ObjectVisitor* visitor) const;
   void VisitObjectPointers(ObjectPointerVisitor* visitor) const;
 
   RawObject* FindObject(FindObjectVisitor* visitor) const;