IndexedDB: Remove outdated TODO.

Bug: 721516
Change-Id: I80ef1e4b11cb44019f2136c60d3bb05431fa7916
Reviewed-on: https://chromium-review.googlesource.com/883979Reviewed-by: Marijn Kruisselbrink <mek@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#531670}

third_party/WebKit/Source/modules/indexeddb/IDBValueWrapping.cpp

@@ -142,8 +142,6 @@ bool IDBValueWrapper::WrapIfBiggerThan(unsigned max_bytes) {
 
   // TODO(pwnall): The MIME type should probably be an atomic string.
   String mime_type(kWrapMimeType);
-  // TODO(crbug.com/721516): Use WebBlobRegistry::CreateBuilder instead of
-  //                         Blob::Create to avoid a buffer copy.
   std::unique_ptr<BlobData> wrapper_blob_data = BlobData::Create();
   wrapper_blob_data->SetContentType(String(kWrapMimeType));
   wrapper_blob_data->AppendBytes(wire_data_.data(), wire_data_size);