WebPositive crashes when uploading large files to Google Drive

[MichaelCrawford]

See also #12807.

I'm unable to use scp to upload the core files for #12807 so I tried emailing them to myself. GMail advises that large files must be shared on Google Drive, with a download link provided in the mail. WebPositive crashes right at the start of the upload.

Two log files are attached.

1. Create a large file; I tried 57 MB and 38 MB.
2. Log into GMail
3. Press the "Compose" button
4. Address the mail to yourself.
5. Press the paperclip icon
6. Select a large file
7. Read the advice that large files must be shared on Google Drive
8. Press OK
9. Crash

The first - larger - file crashed a few seconds after clicking OK. The second immediately after clicking it.