Fix again HeapEntry size problem, now platform-independent way.

src/profile-generator.cc

Index: src/profile-generator.cc
diff --git a/src/profile-generator.cc b/src/profile-generator.cc
index 8e9f13712ea82ada2a54dcc3a5e5c39f7bb5c538..e0b63f950ceebd604386914d2f16a2e1dbb923ed 100644
--- a/src/profile-generator.cc
+++ b/src/profile-generator.cc
@@ -870,16 +870,17 @@ void HeapEntry::Init(HeapSnapshot* snapshot,
   type_ = type;
   painted_ = kUnpainted;
   name_ = name;
-#ifdef WIN32
-  *(reinterpret_cast<uint64_t*>(&id_)) = id;
-#else
-  id_ = id;
-#endif
   self_size_ = self_size;
   retained_size_ = 0;
   children_count_ = children_count;
   retainers_count_ = retainers_count;
   dominator_ = NULL;
+
+  union {
+    uint64_t set_id;
+    Id stored_id;
+  } id_adaptor = {id};
+  id_ = id_adaptor.stored_id;
 }