Split nodes and edges into separate arrays in heap profiler.

src/list-inl.h

Index: src/list-inl.h
diff --git a/src/list-inl.h b/src/list-inl.h
index 35ee3f5e8b8d0d7ba051466bfa56ad9285ceb14b..6cf3badc623b92e20095e208677e3f4d809de5c1 100644
--- a/src/list-inl.h
+++ b/src/list-inl.h
@@ -137,6 +137,14 @@ bool List<T, P>::RemoveElement(const T& elm) {
 
 
 template<typename T, class P>
+void List<T, P>::Allocate(int length) {
+  DeleteData(data_);
+  Initialize(length);
+  length_ = length;
+}
+
+
+template<typename T, class P>
 void List<T, P>::Clear() {
   DeleteData(data_);
   Initialize(0);