Revert of Change ScopedFeatureList to overrides FeatureList not reset

Revert of Change ScopedFeatureList to overrides FeatureList not reset (patchset #6 id:140001 of https://codereview.chromium.org/2834583002/ )

Reason for revert:
Mac ASAN bots reporting use-after-free errors.

Original issue's description:
> Change ScopedFeatureList to overrides FeatureList not reset
> 
> The current situation is that using ScopedFeatureList resets to an
> empty feature list and then enables/disables an explicit list of
> features.
> 
> That's never what you want for browser tests (or other higher-level
> tests) since it effectively overrides higher-level test configurations
> (e.g. those in fieldtrial_testing_config.json, or a bot set up to
> specifically test a feature).
> 
> In this patch:
> 
> 1. Keep SFL::Init, SFL::InitWithFeatureList,
>    SFL::InitFromCommandLine reset to empty list but add warning to
>    remind developer should use them with care.
> 2. Change SFL::InitAndEnableFeature, SFL::InitAndDisableFeature and
>    SFL::InitWithFeatures to not reset but override current FeatureList
>    with given enables/disables.
> 
> We also add unit tests for ScopedFeatureList.
> 
> BUG=713390
> 
> Review-Url: https://codereview.chromium.org/2834583002
> Cr-Commit-Position: refs/heads/master@{#468210}
> Committed: https://chromium.googlesource.com/chromium/src/+/9c04ed553bd7abe820a6a93c5e8981e6738881a9

TBR=isherman@chromium.org,asvitkine@chromium.org,thakis@chromium.org,chaopeng@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=713390
Review-Url: https://codereview.chromium.org/2850073002
Cr-Commit-Position: refs/heads/master@{#468263}
Committed: https://chromium.googlesource.com/chromium/src/+/6c14f269fb196627c72a810205488d694b63a7d5

[Lei Zhang, 2017-04-30 20:58:13]

The CQ bit was checked by thestig@chromium.org

[Lei Zhang, 2017-04-30 20:58:14]

Created Revert of Change ScopedFeatureList to overrides FeatureList not reset

[commit-bot: I haz the power, 2017-04-30 20:58:24]

CQ is trying da patch.

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

[Lei Zhang, 2017-04-30 20:58:47]

Examples of failing bots:

https://build.chromium.org/p/chromium.memory/builders/Mac%20ASan%2064%20Tests...
https://build.chromium.org/p/chromium.mac/builders/Mac10.9%20Tests/builds/40520

[commit-bot: I haz the power, 2017-04-30 22:24:36]

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

[commit-bot: I haz the power, 2017-04-30 22:24:37]

Try jobs failed on following builders:
  linux_chromium_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[Lei Zhang, 2017-04-30 22:36:32]

The CQ bit was checked by thestig@chromium.org

[commit-bot: I haz the power, 2017-04-30 22:36:39]

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, 2017-05-01 00:00:14]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1493591792427980, "parent_rev":
"1d2108cce478cac9751c40efc18e06d12a7a1f2b", "commit_rev":
"6c14f269fb196627c72a810205488d694b63a7d5"}

[commit-bot: I haz the power, 2017-05-01 00:00:29]

Description was changed from

==========
Revert of Change ScopedFeatureList to overrides FeatureList not reset (patchset
#6 id:140001 of https://codereview.chromium.org/2834583002/ )

Reason for revert:
Mac ASAN bots reporting use-after-free errors.

Original issue's description:
> Change ScopedFeatureList to overrides FeatureList not reset
> 
> The current situation is that using ScopedFeatureList resets to an
> empty feature list and then enables/disables an explicit list of
> features.
> 
> That's never what you want for browser tests (or other higher-level
> tests) since it effectively overrides higher-level test configurations
> (e.g. those in fieldtrial_testing_config.json, or a bot set up to
> specifically test a feature).
> 
> In this patch:
> 
> 1. Keep SFL::Init, SFL::InitWithFeatureList,
>    SFL::InitFromCommandLine reset to empty list but add warning to
>    remind developer should use them with care.
> 2. Change SFL::InitAndEnableFeature, SFL::InitAndDisableFeature and
>    SFL::InitWithFeatures to not reset but override current FeatureList
>    with given enables/disables.
> 
> We also add unit tests for ScopedFeatureList.
> 
> BUG=713390
> 
> Review-Url: https://codereview.chromium.org/2834583002
> Cr-Commit-Position: refs/heads/master@{#468210}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9c04ed553bd7abe820a6a93c5e89...

TBR=isherman@chromium.org,asvitkine@chromium.org,thakis@chromium.org,chaopeng...
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=713390
==========

to

==========
Revert of Change ScopedFeatureList to overrides FeatureList not reset (patchset
#6 id:140001 of https://codereview.chromium.org/2834583002/ )

Reason for revert:
Mac ASAN bots reporting use-after-free errors.

Original issue's description:
> Change ScopedFeatureList to overrides FeatureList not reset
> 
> The current situation is that using ScopedFeatureList resets to an
> empty feature list and then enables/disables an explicit list of
> features.
> 
> That's never what you want for browser tests (or other higher-level
> tests) since it effectively overrides higher-level test configurations
> (e.g. those in fieldtrial_testing_config.json, or a bot set up to
> specifically test a feature).
> 
> In this patch:
> 
> 1. Keep SFL::Init, SFL::InitWithFeatureList,
>    SFL::InitFromCommandLine reset to empty list but add warning to
>    remind developer should use them with care.
> 2. Change SFL::InitAndEnableFeature, SFL::InitAndDisableFeature and
>    SFL::InitWithFeatures to not reset but override current FeatureList
>    with given enables/disables.
> 
> We also add unit tests for ScopedFeatureList.
> 
> BUG=713390
> 
> Review-Url: https://codereview.chromium.org/2834583002
> Cr-Commit-Position: refs/heads/master@{#468210}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9c04ed553bd7abe820a6a93c5e89...

TBR=isherman@chromium.org,asvitkine@chromium.org,thakis@chromium.org,chaopeng...
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=713390

Review-Url: https://codereview.chromium.org/2850073002
Cr-Commit-Position: refs/heads/master@{#468263}
Committed:
https://chromium.googlesource.com/chromium/src/+/6c14f269fb196627c72a81020548...
==========

[commit-bot: I haz the power, 2017-05-01 00:00:29]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/6c14f269fb196627c72a81020548...

[chaopeng, 2017-06-28 19:22:18]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/2962963002/ by chaopeng@chromium.org.

The reason for reverting is: Ready for reland..