https://docs.google.com/document/d/1rW9-NkJFTTHx-UlfkPrxtEVr6qqajKl1PgeucigC5y0/edit

Currently we are parsing a data url at WebURLLoaderImpl, but after ResourceLoadViaDataPipe, we need to pass the body for data url via data pipe. However, making a data pipe for each of data url would add some cost of making a pair of data pipe. If we'll put a data pipe reader at ResourceLoader, probably it'd be good to add a logic to parse data url at ResourceLoader.