Add a policy to re-enable deprecated web platform features.

Add a policy to re-enable deprecated web platform features.

This will give admins the ability to re-enable deprecated features
for a limited amount of time.

This is a re-upload of codereview.chromium.org/263423003 because I've taken
over that CL for mnissler.

R=joaodasilva@chromium.org, jochen@chromium.org
TBR=jar
BUG=345831
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=278436

[Andrew T Wilson (Slow), 2014-06-19 00:00:19]

PTAL.

I revamped Mattias' CL to reflect Jochen's and James' feedback. The tests pass
locally (verified with a local copy of blink with ShowModalDialog disabled), and
I'm sending this out so people can take a look while it runs through the bots.

[jamesr, 2014-06-19 00:03:02]

https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
File chrome/test/data/policy/policy_test_cases.json (right):

https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
chrome/test/data/policy/policy_test_cases.json:2118: "os": ["win", "linux",
"mac", "chromeos", "android"],
showmodaldialog has never worked on android

[Andrew T Wilson (Slow), 2014-06-19 00:10:08]

On 2014/06/19 00:03:02, jamesr wrote:
>
https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
> File chrome/test/data/policy/policy_test_cases.json (right):
> 
>
https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
> chrome/test/data/policy/policy_test_cases.json:2118: "os": ["win", "linux",
> "mac", "chromeos", "android"],
> showmodaldialog has never worked on android

Yes, but the "EnableDeprecatedWebPlatformPolicies" policy itself is supported on
android - just not every possible sub-feature is supported.

[Andrew T Wilson (Slow), 2014-06-19 00:13:30]

https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
File chrome/test/data/policy/policy_test_cases.json (right):

https://codereview.chromium.org/344693004/diff/20001/chrome/test/data/policy/...
chrome/test/data/policy/policy_test_cases.json:2118: "os": ["win", "linux",
"mac", "chromeos", "android"],
On 2014/06/19 00:03:02, jamesr wrote:
> showmodaldialog has never worked on android
"android" refers to whether the top-level policy
(EnableDeprecatedWebPlatformFeatures) is supported on Android, so I think
technically it's correct, but after thinking about it a bit I think it's
reasonable to remove it until we have an API that can be re-enabled on that
platform.

[jochen (gone - plz use gerrit), 2014-06-19 00:35:52]

lgtm

[jochen (gone - plz use gerrit), 2014-06-19 00:38:18]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2014-06-19 00:42:02]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/atwilson@chromium.org/344693004/40001

[Andrew T Wilson (Slow), 2014-06-19 07:02:54]

On 2014/06/19 00:42:02, I haz the power (commit-bot) wrote:
> CQ is trying da patch. Follow status at
>  https://chromium-status.appspot.com/cq/atwilson@chromium.org/344693004/40001

Going to TBR jar given the identical change to histograms.xml was already
approved in https://codereview.chromium.org/263423003

[Andrew T Wilson (Slow), 2014-06-19 08:06:38]

The CQ bit was unchecked by atwilson@chromium.org

[Andrew T Wilson (Slow), 2014-06-19 08:08:15]

The CQ bit was checked by atwilson@chromium.org

[commit-bot: I haz the power, 2014-06-19 08:10:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/atwilson@chromium.org/344693004/40001

[Joao da Silva, 2014-06-19 09:11:45]

lgtm

The test can be enabled for ChromeOS in another CL.

https://codereview.chromium.org/344693004/diff/40001/chrome/browser/policy/po...
File chrome/browser/policy/policy_browsertest.cc (right):

https://codereview.chromium.org/344693004/diff/40001/chrome/browser/policy/po...
chrome/browser/policy/policy_browsertest.cc:3007: #endif  // !defined(CHROME_OS)
The new test should be enabled on OS_CHROMEOS too

[commit-bot: I haz the power, 2014-06-19 15:37:35]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-06-19 15:37:36]

Try jobs failed on following builders:
  win_chromium_x64_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/win_chromium_x64_rel/...)

[jochen (gone - plz use gerrit), 2014-06-19 16:19:18]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2014-06-19 16:20:50]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/atwilson@chromium.org/344693004/40001

[Andrew T Wilson (Slow), 2014-06-19 17:48:22]

The CQ bit was checked by atwilson@chromium.org

[commit-bot: I haz the power, 2014-06-19 17:48:48]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/atwilson@chromium.org/344693004/60001

[Andrew T Wilson (Slow), 2014-06-19 18:52:16]

Committed patchset #4 manually as r278436 (presubmit successful).