Rewrite is_linux flag for third_party directory.

This migrates is_linux (which is also set for chromeos) to explicitly
include chromeos as is_linux || is_chromeos in preparation for
separating those flags.

Bug: 1110266
Change-Id: I2820ed1b76d5eed10947d5150a392551efef18c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2326293
Commit-Queue: Sean McAllister <smcallis@google.com>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#793605}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 909c311b1c8a4c9d39ba0c74afee45fba319484c
1 file changed