[WebSocket][nit] Remove an invalid TODO

That's because we've decided not to unify op code and data on a datapipe.

Change-Id: I1d9d83d10108552c6ba04b240ee71c2298d7663e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1903226Reviewed-by: Adam Rice <ricea@chromium.org>
Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713709}

services/network/websocket.cc

@@ -205,7 +205,6 @@ void WebSocket::WebSocketEventHandler::OnDataFrame(
   DVLOG(3) << "WebSocketEventHandler::OnDataFrame @"
            << reinterpret_cast<void*>(this) << " fin=" << fin
            << " type=" << type << " data is " << payload.size() << " bytes";
-  // TODO(yoichio): Merge OnDataFrame mojo channel into data pipe.
   impl_->client_->OnDataFrame(fin, OpCodeToMessageType(type), payload.size());
   if (payload.size() > 0) {
     impl_->pending_data_frames_.push(payload);