Add a feature flag for the new Windows USB backend.

Add a feature flag for the new Windows USB backend.

This will allow development and testing of the new Windows USB backend
while it is still incomplete without disturbing the existing code.

The current implementation of UsbServiceWin is a stub that returns no
devices. UsbServiceImpl retains all of its existing functionality.

BUG=422562
Review-Url: https://codereview.chromium.org/2688303002
Cr-Commit-Position: refs/heads/master@{#450119}
Committed: https://chromium.googlesource.com/chromium/src/+/6204d73a9ba735a29b5f06ff842ea36555e63e78

[Reilly Grant (use Gerrit), 2017-02-11 00:42:10]

The CQ bit was checked by reillyg@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-02-11 00:42:45]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Reilly Grant (use Gerrit), 2017-02-11 00:43:05]

reillyg@chromium.org changed reviewers:
+ scheib@chromium.org

[Reilly Grant (use Gerrit), 2017-02-11 00:43:06]

PTAL

[commit-bot: I haz the power, 2017-02-11 01:02:44]

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

[commit-bot: I haz the power, 2017-02-11 01:02:45]

Dry run: Try jobs failed on following builders:
  android_compile_dbg on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_comp...)

[Reilly Grant (use Gerrit), 2017-02-11 01:08:09]

Fix Android build.

[Reilly Grant (use Gerrit), 2017-02-11 01:11:57]

The CQ bit was checked by reillyg@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-02-11 01:12:44]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[scheib, 2017-02-11 01:45:18]

LGTM, but, maybe can trim the #if guards:

https://codereview.chromium.org/2688303002/diff/20001/chrome/browser/about_fl...
File chrome/browser/about_flags.cc (right):

https://codereview.chromium.org/2688303002/diff/20001/chrome/browser/about_fl...
chrome/browser/about_flags.cc:2214: #if defined(OS_WIN)
Are these #if defined required? IIRC the logic of only showing the flag on the
right platforms is handled by the kOsWin flag that is passed in. I think this
may be cargo culting -- there are examples of other kOsAndroid that don't need
the guards.

[Reilly Grant (use Gerrit), 2017-02-11 01:48:55]

https://codereview.chromium.org/2688303002/diff/20001/chrome/browser/about_fl...
File chrome/browser/about_flags.cc (right):

https://codereview.chromium.org/2688303002/diff/20001/chrome/browser/about_fl...
chrome/browser/about_flags.cc:2214: #if defined(OS_WIN)
On 2017/02/11 01:45:18, scheib wrote:
> Are these #if defined required? IIRC the logic of only showing the flag on the
> right platforms is handled by the kOsWin flag that is passed in. I think this
> may be cargo culting -- there are examples of other kOsAndroid that don't need
> the guards.

The base::Feature instance is defined within #if guards so I can't refer to it
here without them.

[Reilly Grant (use Gerrit), 2017-02-11 02:03:54]

The CQ bit was unchecked by reillyg@chromium.org

[Reilly Grant (use Gerrit), 2017-02-11 02:03:58]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2017-02-11 02:04:17]

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, 2017-02-11 02:34:53]

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

[commit-bot: I haz the power, 2017-02-11 02:34:54]

Try jobs failed on following builders:
  win_chromium_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)

[Reilly Grant (use Gerrit), 2017-02-13 20:37:33]

Update histograms.

[Reilly Grant (use Gerrit), 2017-02-13 20:41:23]

reillyg@chromium.org changed reviewers:
+ holte@chromium.org

[Reilly Grant (use Gerrit), 2017-02-13 20:41:23]

holte@, please review histograms.xml.

[Reilly Grant (use Gerrit), 2017-02-13 20:41:35]

The CQ bit was checked by reillyg@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-02-13 20:42:28]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Steven Holte, 2017-02-13 21:29:21]

histograms lgtm

[Reilly Grant (use Gerrit), 2017-02-13 21:44:34]

The CQ bit was unchecked by reillyg@chromium.org

[Reilly Grant (use Gerrit), 2017-02-13 21:44:40]

The CQ bit was checked by reillyg@chromium.org

[Reilly Grant (use Gerrit), 2017-02-13 21:44:40]

The patchset sent to the CQ was uploaded after l-g-t-m from scheib@chromium.org
Link to the patchset: https://codereview.chromium.org/2688303002/#ps40001
(title: "Update histograms.")

[commit-bot: I haz the power, 2017-02-13 21:44:55]

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, 2017-02-13 22:25:01]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1487022280556220,
"parent_rev": "40c43d4a1edfb1373db775d3637f185f247b06fa", "commit_rev":
"6204d73a9ba735a29b5f06ff842ea36555e63e78"}

[commit-bot: I haz the power, 2017-02-13 22:25:37]

Description was changed from

==========
Add a feature flag for the new Windows USB backend.

This will allow development and testing of the new Windows USB backend
while it is still incomplete without disturbing the existing code.

The current implementation of UsbServiceWin is a stub that returns no
devices. UsbServiceImpl retains all of its existing functionality.

BUG=422562
==========

to

==========
Add a feature flag for the new Windows USB backend.

This will allow development and testing of the new Windows USB backend
while it is still incomplete without disturbing the existing code.

The current implementation of UsbServiceWin is a stub that returns no
devices. UsbServiceImpl retains all of its existing functionality.

BUG=422562

Review-Url: https://codereview.chromium.org/2688303002
Cr-Commit-Position: refs/heads/master@{#450119}
Committed:
https://chromium.googlesource.com/chromium/src/+/6204d73a9ba735a29b5f06ff842e...
==========

[commit-bot: I haz the power, 2017-02-13 22:25:39]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/chromium/src/+/6204d73a9ba735a29b5f06ff842e...