Extracts more information from serial devices on Mac
Extracts more information from serial devices on Mac

At rockot@'s suggestion, I tested this with a small Chrome app that I
wrote (https://github.com/zeptonaut/serial-device-enumerator-app) that
opens a window showing all information that Chrome knows about serial
devices. We chose this route over unit tests because we didn't think
it was wise to write unit tests that assumed specific devices were
plugged into our test servers.

As far as devices, I used an FTDI Chipset High Speed USB 2.0 to Serial
RS-232 DB-9 Converter. This was useful because it's one of not-so-many
devices that has both serial properties (dialin and callout paths) and
USB properties (vendor ID, device ID, and product string).

BUG=522217

Review URL: https://codereview.chromium.org/1306733008

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#348253}

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