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

content/common/dom_storage_messages.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Multiply-included message file, no traditional include guard.
 #include "content/public/common/common_param_traits.h"
 #include "googleurl/src/gurl.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/ipc_param_traits.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebStorageArea.h"
@@ skipping 18 matching lines @@
   // The URL of the page that caused the storage event.
   IPC_STRUCT_MEMBER(GURL, page_url)
 
   // The non-zero connection_id which caused the event or 0 if the event
   // was not caused by the target renderer process.
   IPC_STRUCT_MEMBER(int, connection_id)
 
   // The non-zero session namespace_id associated with the event or 0 if
   // this is a local storage event.
   IPC_STRUCT_MEMBER(int64, namespace_id)
+
+  IPC_STRUCT_MEMBER(int64, storage_size)
 IPC_STRUCT_END()
 
 IPC_ENUM_TRAITS(WebKit::WebStorageArea::Result)
 
 // DOM Storage messages sent from the browser to the renderer.
 
 // Storage events are broadcast to all renderer processes.
 IPC_MESSAGE_CONTROL1(DOMStorageMsg_Event,
                      DOMStorageMsg_Event_Params)
 
 // Completion notification sent in response to each async
 // load, set, remove, and clear operation.
 // Used to maintain the integrity  of the renderer-side cache.
 IPC_MESSAGE_CONTROL1(DOMStorageMsg_AsyncOperationComplete,
                      bool /* success */)
 
 // DOM Storage messages sent from the renderer to the browser.
 // Note: The 'connection_id' must be the first parameter in these message.
 
 // Open the storage area for a particular origin within a namespace.
-IPC_MESSAGE_CONTROL3(DOMStorageHostMsg_OpenStorageArea,
-                     int /* connection_id */,
-                     int64 /* namespace_id */,
-                     GURL /* origin */)
+IPC_SYNC_MESSAGE_CONTROL3_1(DOMStorageHostMsg_OpenStorageArea,
+                            int /* connection_id */,
+                            int64 /* namespace_id */,
+                            GURL /* origin */,
+                            int64 /* storage_size (out) */)
 
 // Close a previously opened storage area.
 IPC_MESSAGE_CONTROL1(DOMStorageHostMsg_CloseStorageArea,
                      int /* connection_id */)
 
 // Retrieves the set of key/value pairs for the area. Used to prime
 // the renderer-side cache. A completion notification is sent in response.
 IPC_SYNC_MESSAGE_CONTROL1_1(DOMStorageHostMsg_LoadStorageArea,
                             int /* connection_id */,
                             dom_storage::ValuesMap)
@@ skipping 13 matching lines @@
                      string16 /* key */,
                      GURL /* page_url */)
 
 // Clear the storage area. A completion notification is sent in response.
 IPC_MESSAGE_CONTROL2(DOMStorageHostMsg_Clear,
                      int /* connection_id */,
                      GURL /* page_url */)
 
 // Used to flush the ipc message queue.
 IPC_SYNC_MESSAGE_CONTROL0_0(DOMStorageHostMsg_FlushMessages)