owncloud/core

Bugfix: Store checksums only if the whole stream has been read

Previously, range downloads (or downloads requesting a specific
byte range) would store a checksum, if needed, based only on the
requested range. This causes problems because the checksum is
expected to be for the whole file.

Now, those range downloads won't store a checksum because only a
part of the file has been read, so the checksum would be incomplete.

Some additional cases have been taken into account, mostly based
on actions that could happen on the data stream, but they shouldn't
happen normally.

https://github.com/owncloud/core/pull/40513