[BlobAsync] Disk support for blob storage

content/common/fileapi/webblob_messages.h

Index: content/common/fileapi/webblob_messages.h
diff --git a/content/common/fileapi/webblob_messages.h b/content/common/fileapi/webblob_messages.h
index 85dbf8c976c17d1cdd11158cbf30c2819fd2be7d..796795ba419d93ae869463bb77537b3d38049416 100644
--- a/content/common/fileapi/webblob_messages.h
+++ b/content/common/fileapi/webblob_messages.h
@@ -48,21 +48,17 @@ IPC_STRUCT_TRAITS_BEGIN(storage::BlobItemBytesResponse)
   IPC_STRUCT_TRAITS_MEMBER(time_file_modified)
 IPC_STRUCT_TRAITS_END()
 
-// This message is to tell the browser that we will be building a blob.
-IPC_MESSAGE_CONTROL4(BlobStorageMsg_RegisterBlobUUID,
-                     std::string /* uuid */,
-                     std::string /* content_type */,
-                     std::string /* content_disposition */,
-                     std::set<std::string> /* referenced_blob_uuids */)
-
-// The DataElements are used to:
+// This message is to tell the browser that we will be building a blob. The
+// DataElements are used to:
 // * describe & transport non-memory resources (blobs, files, etc)
 // * describe the size of memory items
 // * 'shortcut' transport the memory up to the IPC limit so the browser can use
 //   it if it's not currently full.
 // See https://bit.ly/BlobStorageRefactor
-IPC_MESSAGE_CONTROL2(BlobStorageMsg_StartBuildingBlob,
+IPC_MESSAGE_CONTROL4(BlobStorageMsg_RegisterBlob,
                      std::string /* uuid */,
+                     std::string /* content_type */,
+                     std::string /* content_disposition */,
                      std::vector<storage::DataElement> /* item_descriptions */)
 
 IPC_MESSAGE_CONTROL4(