The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/392484cfd0bb44ee1606071fbe39c23b5934798f

commit 392484cfd0bb44ee1606071fbe39c23b5934798f
Author: rdevlin.cronin <rdevlin.cronin@chromium.org>
Date: Wed Jul 19 18:46:44 2017

[Extensions] Fix platforms for privacy.websites.protectedContentEnabled

privacy.websites.protectedContentEnabled is enabled per-platform, and
the platform list includes "cros" and "cros touch". But the
determination of the platforms in binding.js includes "chromeos" and
"chromeos touch". As a result, the protectedContentEnabled feature
is never actually available on a CrOS platform (despite being documented
as such).

It appears that, since it's addition in
https://crrev.com/cc3a5c8ca42579c0f9f710c18f51c566b4c75e86, this has
been unavailable on ChromeOS: See
https://chromium.googlesource.com/chromium/src/+/cc3a5c8ca42579c0f9f710c18f51c566b4c75e86/chrome/renderer/resources/extensions/schema_generated_bindings.js#318
and
https://chromium.googlesource.com/chromium/src/+/cc3a5c8ca42579c0f9f710c18f51c566b4c75e86/chrome/common/extensions/api/privacy.json#88
where the patch was added.

Update the platforms listed to be those that are used in the features
system.

Also update the browser test to correctly check the
privacy.websites.protectedContentEnabled feature on all platforms, as
well as expanding it to test setting preferences.

BUG= 746064 

Review-Url: https://codereview.chromium.org/2966613002
Cr-Commit-Position: refs/heads/master@{#487931}

[modify] https://crrev.com/392484cfd0bb44ee1606071fbe39c23b5934798f/chrome/common/extensions/api/privacy.json
[modify] https://crrev.com/392484cfd0bb44ee1606071fbe39c23b5934798f/chrome/test/data/extensions/api_test/preference/standard/test.js