Break large blobs into multiple ipcs during creation.

content/common/webblob_messages.h

 // Copyright (c) 2011 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.
 
 // IPC messages for HTML5 Blob.
 // Multiply-included message file, hence no include guard.
 
 #include "content/common/common_param_traits.h"
 #include "content/common/webkit_param_traits.h"
 #include "ipc/ipc_message_macros.h"
 
 #define IPC_MESSAGE_START BlobMsgStart
 
+IPC_ENUM_TRAITS(webkit_blob::BlobData::Type)
+
+IPC_STRUCT_TRAITS_BEGIN(webkit_blob::BlobData::Item)
+  IPC_STRUCT_TRAITS_MEMBER(type_)
+  IPC_STRUCT_TRAITS_MEMBER(data_)
+  IPC_STRUCT_TRAITS_MEMBER(file_path_)
+  IPC_STRUCT_TRAITS_MEMBER(blob_url_)
+  IPC_STRUCT_TRAITS_MEMBER(offset_)
+  IPC_STRUCT_TRAITS_MEMBER(length_)
+  IPC_STRUCT_TRAITS_MEMBER(expected_modification_time_)
+IPC_STRUCT_TRAITS_END()
+
 // Blob messages sent from the renderer to the browser.
 
+
 // Registers a blob URL referring to the specified blob data.
-IPC_MESSAGE_CONTROL2(BlobHostMsg_RegisterBlobUrl,
+IPC_MESSAGE_CONTROL1(BlobHostMsg_RegisterUnfinalizedBlobUrl,
+                     GURL /* url */)
+
+// Appends data to an unfinalized blob.
+IPC_MESSAGE_CONTROL2(BlobHostMsg_AppendBlobDataItem,
                      GURL /* url */,
-                     scoped_refptr<webkit_blob::BlobData> /* blob_data */)
+                     webkit_blob::BlobData::Item)
+
+// Finalizes a blob.
+IPC_MESSAGE_CONTROL2(BlobHostMsg_FinalizeBlob,
+                     GURL /* url */,
+                     std::string /* content_type */)
 
 // Registers a blob URL referring to the blob data identified by the specified
-// source URL.
+// source URL. The source URL must be a finalized blob.
 IPC_MESSAGE_CONTROL2(BlobHostMsg_RegisterBlobUrlFrom,
                      GURL /* url */,
                      GURL /* src_url */)
 
-// Unregister a blob URL.
+// Unregister a blob URL, finalized or unfinalized.
 IPC_MESSAGE_CONTROL1(BlobHostMsg_UnregisterBlobUrl,
                      GURL /* url */)