The chromium-side backchannel plumbing for blobs in IDB.

content/common/indexed_db/indexed_db_messages.h

Index: content/common/indexed_db/indexed_db_messages.h
diff --git a/content/common/indexed_db/indexed_db_messages.h b/content/common/indexed_db/indexed_db_messages.h
index ac3fa2bcac98515715105ef910fde834953d81ed..8570182bf51c0bc580d15c43fff4b2f1698ccc59 100644
--- a/content/common/indexed_db/indexed_db_messages.h
+++ b/content/common/indexed_db/indexed_db_messages.h
@@ -271,6 +271,8 @@ IPC_STRUCT_BEGIN(IndexedDBMsg_CallbacksSuccessCursorPrefetch_Params)
   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> >,