postmortem: export private field offsets

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index 79988f8f27a9a0c45f7d66fd4c2df9b46c4b81f0..2663246041c4ba18ea19f9a7d0170744d7e91f64 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -67,6 +67,7 @@ class InnerPointerToCodeCache;
 class Logger;
 class MaterializedObjectStore;
 class CodeAgingHelper;
+class PostMortem;
 class RegExpStack;
 class SaveContext;
 class StatsTable;
@@ -1358,6 +1359,9 @@ class Isolate {
   friend class v8::Unlocker;
   friend v8::StartupData v8::V8::CreateSnapshotDataBlob(const char*);
 
+  // Used in postmortem
+  friend class PostMortem;
+
   DISALLOW_COPY_AND_ASSIGN(Isolate);
 };