Finch kill switch feature for background tab.

Finch kill switch feature for background tab.

Adds the CCTBackgroundTab (ChromeFeatureList::CCT_BACKGROUND_TAB) feature
which is enabled by default.

BUG=708173
Review-Url: https://codereview.chromium.org/2837873002
Cr-Commit-Position: refs/heads/master@{#467281}
Committed: https://chromium.googlesource.com/chromium/src/+/d9b19c661ed366be0c901cc45257160986bab530

[mattcary, 2017-04-24 15:45:52]

mattcary@chromium.org changed reviewers:
+ lizeb@chromium.org

[mattcary, 2017-04-24 15:45:52]

Benoit--

Here's the kill-switch CL. Note that I've started a conversation about apparent
ChromeFeatureList owners about my isEnabled change which appears to be necessary
to get tests to work. Probably I would break that out into its own CL but I
don't know how long the conversation will take.

I don't know if the test is strictly necessary---tests on flipping feature bits
seem to be few and far between---but it's not a bad idea. LMK if it would be
more expedient to break out the test from the flag, though, given the test
support issues.

[Benoit L, 2017-04-24 16:18:00]

Thanks!

lgtm

https://codereview.chromium.org/2837873002/diff/1/chrome/android/javatests/sr...
File
chrome/android/javatests/src/org/chromium/chrome/browser/customtabs/CustomTabActivityTest.java
(right):

https://codereview.chromium.org/2837873002/diff/1/chrome/android/javatests/sr...
chrome/android/javatests/src/org/chromium/chrome/browser/customtabs/CustomTabActivityTest.java:1829:
ChromeFeatureList.setTestFeatures(features);
Should this be reset in a finally block?

Seems that the annotation sets the list to null.

[mattcary, 2017-04-24 16:33:43]

I just realized that this is using base::feature_list.h, and that we should be
using a field trial instead? Or are field trials not easily accessible from
java?

I can dig, but if you just know the answer, so much the better.

As for the ChromeFeatureList stuff, bauerb@ points out that using
@CommandlineFlags.Add(...) would be better than ChromeFeatureList as it would
plumb it all the way down to native.

[mattcary, 2017-04-25 14:48:12]

Updated to use command line changer which solves all sorts of problems.

Also resolved my question offline about finch experiments; I am indeed doing it
correctly this way.

[mattcary, 2017-04-26 08:38:56]

The CQ bit was checked by mattcary@chromium.org

[mattcary, 2017-04-26 08:38:56]

The patchset sent to the CQ was uploaded after l-g-t-m from lizeb@chromium.org
Link to the patchset: https://codereview.chromium.org/2837873002/#ps20001
(title: "Use command-line arg changer")

[commit-bot: I haz the power, 2017-04-26 08:39:08]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-04-26 08:42:00]

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

[commit-bot: I haz the power, 2017-04-26 08:42:01]

Try jobs failed on following builders:
  android_arm64_dbg_recipe on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_arm6...)
  chromium_presubmit on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[mattcary, 2017-04-26 08:51:39]

The CQ bit was checked by mattcary@chromium.org

[mattcary, 2017-04-26 08:51:39]

The patchset sent to the CQ was uploaded after l-g-t-m from lizeb@chromium.org
Link to the patchset: https://codereview.chromium.org/2837873002/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2017-04-26 08:51:49]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-04-26 09:30:18]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1493196699240880,
"parent_rev": "136356dc7ed7b595ed2e0b63d968a7a27171468c", "commit_rev":
"d9b19c661ed366be0c901cc45257160986bab530"}

[commit-bot: I haz the power, 2017-04-26 09:30:28]

Description was changed from

==========
Finch kill switch feature for background tab.

Adds the CCTBackgroundTab (ChromeFeatureList::CCT_BACKGROUND_TAB) feature
which is enabled by default.

BUG=708173
==========

to

==========
Finch kill switch feature for background tab.

Adds the CCTBackgroundTab (ChromeFeatureList::CCT_BACKGROUND_TAB) feature
which is enabled by default.

BUG=708173

Review-Url: https://codereview.chromium.org/2837873002
Cr-Commit-Position: refs/heads/master@{#467281}
Committed:
https://chromium.googlesource.com/chromium/src/+/d9b19c661ed366be0c901cc45257...
==========

[commit-bot: I haz the power, 2017-04-26 09:30:30]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/chromium/src/+/d9b19c661ed366be0c901cc45257...