Persist sessionStorage on disk.

webkit/dom_storage/dom_storage_session.h

Index: webkit/dom_storage/dom_storage_session.h
diff --git a/webkit/dom_storage/dom_storage_session.h b/webkit/dom_storage/dom_storage_session.h
index c6694b7d903890240926fbedc880a6b336186283..b2dd941d89463bb81aafe94a7b22cea3c59082ed 100644
--- a/webkit/dom_storage/dom_storage_session.h
+++ b/webkit/dom_storage/dom_storage_session.h
@@ -8,11 +8,10 @@
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
+#include "webkit/dom_storage/dom_storage_context.h"
 
 namespace dom_storage {
 
-class DomStorageContext;
-
 // This refcounted class determines the lifetime of a session
 // storage namespace and provides an interface to Clone() an
 // existing session storage namespace. It may be used on any thread.
@@ -24,6 +23,11 @@ class DomStorageSession
   int64 namespace_id() const { return namespace_id_; }
   DomStorageSession* Clone();
 
+  void AddSessionStorageObserver(
+      int64 namespace_id,
+      DomStorageContext::SessionStorageObserver* observer);
+  void RemoveSessionStorageObserver(int64 namespace_id);
+
  private:
   friend class base::RefCountedThreadSafe<DomStorageSession>;
 
@@ -33,6 +37,8 @@ class DomStorageSession
   scoped_refptr<DomStorageContext> context_;
   int64 namespace_id_;
 
+  DomStorageContext::SessionStorageObserver* observer_;
+
   DISALLOW_IMPLICIT_CONSTRUCTORS(DomStorageSession);
 };