Move SessionStorageNamespace entirely into NavigationController and support StoragePartitions.

content/browser/dom_storage/session_storage_namespace_impl.h

Index: content/browser/dom_storage/session_storage_namespace_impl.h
diff --git a/content/browser/dom_storage/session_storage_namespace_impl.h b/content/browser/dom_storage/session_storage_namespace_impl.h
index f075b546a7feae08671f84d5c3ebd6b4237c06b3..e0977083de80e041af62775fa03fc60f938eaa4d 100644
--- a/content/browser/dom_storage/session_storage_namespace_impl.h
+++ b/content/browser/dom_storage/session_storage_namespace_impl.h
@@ -16,7 +16,7 @@ namespace dom_storage {
 class DomStorageSession;
 }
 
-class SessionStorageNamespaceImpl
+class CONTENT_EXPORT SessionStorageNamespaceImpl
     : NON_EXPORTED_BASE(public content::SessionStorageNamespace) {
  public:
   // Constructs a |SessionStorageNamespaceImpl| and allocates new IDs for it.
@@ -38,6 +38,7 @@ class SessionStorageNamespaceImpl
   virtual void SetShouldPersist(bool should_persist) OVERRIDE;
 
   SessionStorageNamespaceImpl* Clone();
+  bool IsFromContext(DOMStorageContextImpl* context);
 
  private:
   explicit SessionStorageNamespaceImpl(dom_storage::DomStorageSession* clone);