The chromium-side backchannel plumbing for blobs in IDB.

content/common/indexed_db/indexed_db_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.
 
 // Message definition file, included multiple times, hence no include guard.
 
 #include <utility>
 #include <vector>
 
 #include "content/common/indexed_db/indexed_db_key.h"
@@ skipping 253 matching lines @@
   // Sideband data for any blob or file encoded in value.
   IPC_STRUCT_MEMBER(std::vector<IndexedDBMsg_BlobOrFileInfo>, blob_or_file_info)
 IPC_STRUCT_END()
 
 IPC_STRUCT_BEGIN(IndexedDBMsg_CallbacksSuccessCursorPrefetch_Params)
   IPC_STRUCT_MEMBER(int32, ipc_thread_id)
   IPC_STRUCT_MEMBER(int32, ipc_callbacks_id)
   IPC_STRUCT_MEMBER(int32, ipc_cursor_id)
   IPC_STRUCT_MEMBER(std::vector<content::IndexedDBKey>, keys)
   IPC_STRUCT_MEMBER(std::vector<content::IndexedDBKey>, primary_keys)
+  // TODO(ericu): Put each value/vector<blob_info> together in a wrapper object,

[jsbell, 2014/04/17 22:05:56]

We'd want to tackle all 4 vectors, not just value/vector<blob_info>.

I found my old patch and it was using a Tuple3 but I thought a dedicated struct
was a better idea at that point and abandoned it.

(If you add a TODO you'll need to get tsepez to sign off or TBR. Maybe just file
a bug?)

[ericu, 2014/04/17 22:08:08]

Oh right--of course.
Will do.

+  // so we don't have to check that we've got same-length arrays of each.
   IPC_STRUCT_MEMBER(std::vector<std::string>, values)
   // Sideband data for any blob or file encoded in value.
   IPC_STRUCT_MEMBER(std::vector<std::vector<IndexedDBMsg_BlobOrFileInfo> >,
                     blob_or_file_infos)
 IPC_STRUCT_END()
 
 IPC_STRUCT_BEGIN(IndexedDBMsg_CallbacksSuccessValue_Params)
   IPC_STRUCT_MEMBER(int32, ipc_thread_id)
   IPC_STRUCT_MEMBER(int32, ipc_callbacks_id)
   IPC_STRUCT_MEMBER(std::string, value)
@@ skipping 253 matching lines @@
                      int64) /* transaction_id */
 
 // WebIDBDatabase::commit() message.
 IPC_MESSAGE_CONTROL2(IndexedDBHostMsg_DatabaseCommit,
                      int32, /* ipc_database_id */
                      int64) /* transaction_id */
 
 // WebIDBDatabase::~WebIDBCursor() message.
 IPC_MESSAGE_CONTROL1(IndexedDBHostMsg_CursorDestroyed,
                      int32 /* ipc_cursor_id */)