This is a reland of commit 5e49eda5

Original change's description:
> Break make_encoded_file into two functions
>
> The python3 fallback for `make_encoded_file()` produces different results on py2 and py3 when bytes are passed. This CL makes it clear breaking it into two methods, one for text and another for bytes. This CL also adds a fallback in `download_file` for py3 to return bytes when it cannot decode the downloaded file into utf-8.
>
> Recipe-Manual-Change: chromiumos
> Change-Id: I3d313e430c852e179825bc24bf4a58ce84440b2a
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3595026
> Reviewed-by: Gavin Mak <gavinmak@google.com>
> Reviewed-by: Greg Edelston <gredelston@google.com>
> Commit-Queue: Aravind Vasudevan <aravindvasudev@google.com>

Recipe-Manual-Change: chromiumos
Change-Id: I2de85eca71cc45f503c25888297ba881a5c662a8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3610973Reviewed-by: Aravind Vasudevan <aravindvasudev@google.com>
Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Greg Edelston <gredelston@google.com>