MemoryError when scanning 100 MiB single-line JSON file

Slightly related to #616 (which is about the json2csv tool), I also see an error when scanning a (close to) 100 MiB JSON file with ScanCode version 2.2.1.post277.4d68f9377, on both Linux and Windows. I'm wondering whether ScanCode is still trying to interpret the JSON instead of handling it as a BLOB despite my not specifying the `--package` option, and whether that's causing the huge memory usage.

My full command line is

scancode --copyright --license --license-text --info --only-findings --strip-root --timeout 300 --processes 15 /dir/to/scan --json-pp result.json

Answering @pombredanne's question from #616:

> JSON should not be treated as plain data when this is compact, single line.
> Is this file a single line, like a huge js.map map file?

Yes, it is.