DRP metrics observer stop observing after hidden

DRP metrics observer stop observing after hidden

This calls SendPingback when the tab is first hidden instead of waiting
until the tab is closed. The pingback only carries information about
events that happen before hidden.

This also allows for some simplification (knowing callbacks will only be
called before hidden has happened).

BUG=618072
Committed: https://crrev.com/0b2687efe4b3b81aad36cb61d814f45474b1173a
Cr-Commit-Position: refs/heads/master@{#430070}

[RyanSturm, 2016-11-04 20:52:37]

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

[commit-bot: I haz the power, 2016-11-04 20:53:17]

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

[RyanSturm, 2016-11-04 21:08:46]

ryansturm@chromium.org changed reviewers:
+ bmcquade@chromium.org

[RyanSturm, 2016-11-04 21:08:46]

bmcquade: PTAL, I added timing and info to OnHidden. I can switch to consuming
FlushMetrics instead of OnHidden if that makes more sense, and we will still
wait for the tab to close on desktop.

[Bryan McQuade, 2016-11-04 22:42:57]

this is great to see, thanks!

https://codereview.chromium.org/2478903002/diff/1/chrome/browser/page_load_me...
File
chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
(right):

https://codereview.chromium.org/2478903002/diff/1/chrome/browser/page_load_me...
chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc:117:
page_load_metrics::PageLoadMetricsObserver::ObservePolicy
great! we should also implement OnStart and return STOP_OBSERVING if the boolean
foreground/background param indicates we started in background.

[RyanSturm, 2016-11-04 22:51:53]

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

[commit-bot: I haz the power, 2016-11-04 22:53:28]

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

[RyanSturm, 2016-11-04 22:54:06]

bmcquade: PTAL

https://codereview.chromium.org/2478903002/diff/1/chrome/browser/page_load_me...
File
chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc
(right):

https://codereview.chromium.org/2478903002/diff/1/chrome/browser/page_load_me...
chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.cc:117:
page_load_metrics::PageLoadMetricsObserver::ObservePolicy
On 2016/11/04 22:42:56, Bryan McQuade wrote:
> great! we should also implement OnStart and return STOP_OBSERVING if the
boolean
> foreground/background param indicates we started in background.

Done.

[Bryan McQuade, 2016-11-04 23:10:32]

LGTM, thanks!

[RyanSturm, 2016-11-04 23:15:47]

The CQ bit was unchecked by ryansturm@chromium.org

[RyanSturm, 2016-11-04 23:15:49]

The CQ bit was checked by ryansturm@chromium.org

[commit-bot: I haz the power, 2016-11-04 23:16:16]

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, 2016-11-05 00:10:09]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-11-05 00:14:04]

Description was changed from

==========
DRP metrics observer stop observing after hidden

This calls SendPingback when the tab is first hidden instead of waiting
until the tab is closed. The pingback only carries information about
events that happen before hidden.

This also allows for some simplification (knowing callbacks will only be
called before hidden has happened).

BUG=618072
==========

to

==========
DRP metrics observer stop observing after hidden

This calls SendPingback when the tab is first hidden instead of waiting
until the tab is closed. The pingback only carries information about
events that happen before hidden.

This also allows for some simplification (knowing callbacks will only be
called before hidden has happened).

BUG=618072

Committed: https://crrev.com/0b2687efe4b3b81aad36cb61d814f45474b1173a
Cr-Commit-Position: refs/heads/master@{#430070}
==========

[commit-bot: I haz the power, 2016-11-05 00:14:05]

Patchset 2 (id:??) landed as
https://crrev.com/0b2687efe4b3b81aad36cb61d814f45474b1173a
Cr-Commit-Position: refs/heads/master@{#430070}