New metric to track usage of the new GAIA flow.

New metric to track usage of the new GAIA flow.

BUG=464051
Committed: https://crrev.com/97f445516b8c834ab30955a7b0386d0de393e2b9
Cr-Commit-Position: refs/heads/master@{#320880}

[Ivan Podogov, 2015-03-13 19:07:40]

ginkage@chromium.org changed reviewers:
+ dpolukhin@chromium.org, isherman@chromium.org

[Ivan Podogov, 2015-03-13 19:07:50]

PTAL

[Ilya Sherman, 2015-03-13 23:11:34]

I'm a little confused -- are users choosing which endpoint they hit?  If so, why
is this user-configurable?

I wonder whether you might not get more representative data by measuring the
rate on the server-side rather than just for UMA users on the client-side.

https://codereview.chromium.org/1009453003/diff/1/tools/metrics/histograms/hi...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/1009453003/diff/1/tools/metrics/histograms/hi...
tools/metrics/histograms/histograms.xml:2788: +    Whether a user signed in
using the new WebView-based GAIA flow.
Please document when this is reported.

[Ivan Podogov, 2015-03-14 14:16:06]

On 2015/03/13 23:11:34, Ilya Sherman wrote:
> I'm a little confused -- are users choosing which endpoint they hit?  If so,
why
> is this user-configurable?

This is available as a dogfood option, only for the pre-stable channels of
ChromeOS.

> I wonder whether you might not get more representative data by measuring the
> rate on the server-side rather than just for UMA users on the client-side.

On the server side it might be a little harder to extract the data subset that
we are looking for: only ChromeOS, only our GAIA screen, when authentication is
complete. On our side we have all the endpoints in one class, and are able to
report them easily, right when it's needed.

>
https://codereview.chromium.org/1009453003/diff/1/tools/metrics/histograms/hi...
> File tools/metrics/histograms/histograms.xml (right):
> 
>
https://codereview.chromium.org/1009453003/diff/1/tools/metrics/histograms/hi...
> tools/metrics/histograms/histograms.xml:2788: +    Whether a user signed in
> using the new WebView-based GAIA flow.
> Please document when this is reported.

[Ilya Sherman, 2015-03-17 01:50:14]

LGTM

[Dmitry Polukhin, 2015-03-17 07:30:01]

lgtm

[Ivan Podogov, 2015-03-17 07:34:50]

The CQ bit was checked by ginkage@chromium.org

[commit-bot: I haz the power, 2015-03-17 07:34:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1009453003/20001

[commit-bot: I haz the power, 2015-03-17 08:49:21]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-17 08:50:05]

Patchset 2 (id:??) landed as
https://crrev.com/97f445516b8c834ab30955a7b0386d0de393e2b9
Cr-Commit-Position: refs/heads/master@{#320880}