GitLab

piex-wasm assumes a fileSystemURL input as the RAW image source. Allow
other users to input the RAW image source in a File.

Add readFile helper, and make fileSystemURL and File source inputs use
it to read the file.

fileSystemURL case has automated test coverage, so readFIle is tested,
so no change in files app behavior.

Bug: 1132695
Change-Id: Ic05c5b5a2178826445221448824f8ef41dc81ea7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2437084Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Trent Apted <tapted@chromium.org>
Auto-Submit: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811898}