Do not assume that names of function expressions are context-allocated.

src/profile-generator.cc

Index: src/profile-generator.cc
diff --git a/src/profile-generator.cc b/src/profile-generator.cc
index 683fec15bb98afc281ce2a1b15eb9f4c35e0eb65..e895cccdfc4b58e62681b091117c0c1e17396bb9 100644
--- a/src/profile-generator.cc
+++ b/src/profile-generator.cc
@@ -2109,12 +2109,11 @@ void V8HeapExplorer::ExtractClosureReferences(JSObject* js_obj,
     // Add function variable.
     if (scope_info->HasFunctionName()) {
       String* name = scope_info->FunctionName();
-      int idx = Context::MIN_CONTEXT_SLOTS + context_locals;
-#ifdef DEBUG
       VariableMode mode;
-      ASSERT(idx == scope_info->FunctionContextSlotIndex(name, &mode));
-#endif
-      SetClosureReference(js_obj, entry, name, context->get(idx));
+      int idx = scope_info->FunctionContextSlotIndex(name, &mode);
+      if (idx >= 0) {
+        SetClosureReference(js_obj, entry, name, context->get(idx));
+      }
     }
   }
 }