Limiting response size doesn't work when streaming a file with cURL

[bradyvercher]

The functionality for limiting the response size from an HTTP request was introduced in #23472

However, it doesn't work when stream is set to true and cURL is the transport. I've attached a plugin that'll try to limit the response to 32KB and stream an MP3 to a temporary file. Currently, it downloads the whole file

The attached patch should fix the behavior when using cURL, but I haven't tested the other transports.

[dd32]

$this->bytes_written_total .= $bytes_written; should probably be += but other than that, looks sane to me.

Streams should work as-is already by the looks of it.

[bradyvercher]

Replying to dd32:

$this->bytes_written_total .= $bytes_written; should probably be += but other than that, looks sane to me.

Whoops, good catch.

[dd32]

In 29968:

HTTP API: Support both the 'limit_response_size' and 'stream' parameters at the same time, allowing a partial file download.
Fixes #26726

[DrewAPicture]

In 30767:

Fix a typo in the DocBlock for WP_Http_Curl::$bytes_written_total introduced in [29968].

Props kpdesign.
See #26726.