Purge in-memory localStorage areas if the # of areas exceeds the limit

webkit/dom_storage/dom_storage_types.h

Index: webkit/dom_storage/dom_storage_types.h
diff --git a/webkit/dom_storage/dom_storage_types.h b/webkit/dom_storage/dom_storage_types.h
index 180fb8043dfae553d6f2689463a81d1af83bfcfe..b449c10ff0e9e7e01a8533c2d606c8dc8aad0c18 100644
--- a/webkit/dom_storage/dom_storage_types.h
+++ b/webkit/dom_storage/dom_storage_types.h
@@ -30,6 +30,13 @@ const size_t kPerAreaOverQuotaAllowance = 100 * 1024;
 // values for sessionstorage namespaces.
 const int64 kLocalStorageNamespaceId = 0;
 
+// Max in-memory storage size.  One profile (i.e. one DomStorageContext)
+// should not hold in-memory data more than this.
+// TODO(kinuko,michaeln): Consider calling DomStorageArea::PurgeMemory
+// at a reasonable timing to keep the in-memory cache size rather than
+// rejecting incoming requests.
+const size_t kMaxInMemoryAreaSize = 512 * 1024 * 1024;
+
 const int64 kInvalidSessionStorageNamespaceId = kLocalStorageNamespaceId;
 
 // Value to indicate an area that not be opened.