Use the Streams API for file Blobs, instead of FileReader, to allow
large files to be loaded in chunks.

Change-Id: I241e0daff3f9c3d491dde2f3e8e52ea2236f05be
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2953286
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75095}