* Only pass -t to adb if running with stdout as a tty (prevents weird
   tty output processing, .e.g replacing '\n' with '\r\n')
 * Allow passing a device directory for d8 (useful for testing multiple
   builds against each other)
 * Allow specifying additional allowed paths (useful for e.g. running
   files from /tmp)

Change-Id: I90b8bba6f3c248105927c800b8b5b601692adf6c
Reviewed-on: https://chromium-review.googlesource.com/629079
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47576}