[Android] Force enable battery updates instead of resetting to clear power data.

[Android] Force enable battery updates instead of resetting to clear power data.

adb over wifi is broken for power measurements. This should fix it.

BUG=497238
Committed: https://crrev.com/3cb62af5067cc8bf6ffa787b458edc838962ffae
Cr-Commit-Position: refs/heads/master@{#333633}

[rnephew (Reviews Here), 2015-06-05 20:11:28]

rnephew@chromium.org changed reviewers:
+ fmeawad@chromium.org, jbudorick@chromium.org

[jbudorick, 2015-06-09 18:29:16]

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
File build/android/pylib/device/battery_utils.py (left):

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
build/android/pylib/device/battery_utils.py:292: ['dumpsys', 'battery',
'reset'], check_return=True)
Is there anything covered by reset that isn't covered by set usb 1 and set ac 1?

[rnephew (Reviews Here), 2015-06-09 19:07:29]

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
File build/android/pylib/device/battery_utils.py (left):

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
build/android/pylib/device/battery_utils.py:292: ['dumpsys', 'battery',
'reset'], check_return=True)
On 2015/06/09 18:29:16, jbudorick wrote:
> Is there anything covered by reset that isn't covered by set usb 1 and set ac
1?

The only purpose of the reset here is to make sure the phone was aware it was
charging, so that when you run the batterystats --reset command it will not
start adding new power right away and fail the 'did power reset' check. When
using adb over wifi, resetting just leaves it in a state where its not charging
so the 'did power reset' check fails since as soon as it is cleared, it starts
adding new measurements. 

The battery reset in EnableBatteryUpdates is the important one, since it is for
actually resetting the battery state.

[jbudorick, 2015-06-09 19:09:45]

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
File build/android/pylib/device/battery_utils.py (left):

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
build/android/pylib/device/battery_utils.py:292: ['dumpsys', 'battery',
'reset'], check_return=True)
On 2015/06/09 at 19:07:29, rnephew1 wrote:
> On 2015/06/09 18:29:16, jbudorick wrote:
> > Is there anything covered by reset that isn't covered by set usb 1 and set
ac 1?
> 
> The only purpose of the reset here is to make sure the phone was aware it was
charging, so that when you run the batterystats --reset command it will not
start adding new power right away and fail the 'did power reset' check. When
using adb over wifi, resetting just leaves it in a state where its not charging
so the 'did power reset' check fails since as soon as it is cleared, it starts
adding new measurements. 
> 
> The battery reset in EnableBatteryUpdates is the important one, since it is
for actually resetting the battery state.

I take it that the dumpsys battery reset in EnableBatteryUpdates will work on
wifi?

[rnephew (Reviews Here), 2015-06-09 19:16:18]

> I take it that the dumpsys battery reset in EnableBatteryUpdates will work on
> wifi?

Yes. The EnableBatteryUpdate function does not clear the power data, so it does
not check that it has been cleared. It just resets the battery to the correct
state and enables listening for state changes(ie, plugging the phone in). In the
case of usb, it sees that it is charging and changes to that state, and for over
wifi it sees that it is still not charging.

[jbudorick, 2015-06-09 20:58:07]

lgtm

[rnephew (Reviews Here), 2015-06-09 20:59:17]

The CQ bit was checked by rnephew@chromium.org

[commit-bot: I haz the power, 2015-06-09 20:59:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1153143007/20001

[commit-bot: I haz the power, 2015-06-10 01:20:23]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-06-10 01:21:13]

Patchset 2 (id:??) landed as
https://crrev.com/3cb62af5067cc8bf6ffa787b458edc838962ffae
Cr-Commit-Position: refs/heads/master@{#333633}

[sri, 2015-06-10 17:34:02]

srikumar.b@gmail.com changed reviewers:
+ srikumar.b@gmail.com

[sri, 2015-06-10 17:34:02]

Posted a review comment

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
File build/android/pylib/device/battery_utils.py (right):

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
build/android/pylib/device/battery_utils.py:335:
timeout_retry.WaitFor(battery_updates_enabled, wait_period=1)
With this change, The above command fails because we are checking for
"self.GetCharging() is True" after "battery reset" but the device is not
expected to charge even after reset (Because we are testing the scenario where
the device is not charging at all)

[rnephew (Reviews Here), 2015-06-10 17:59:55]

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
File build/android/pylib/device/battery_utils.py (right):

https://codereview.chromium.org/1153143007/diff/20001/build/android/pylib/dev...
build/android/pylib/device/battery_utils.py:335:
timeout_retry.WaitFor(battery_updates_enabled, wait_period=1)
On 2015/06/10 17:34:02, sri wrote:
> With this change, The above command fails because we are checking for
> "self.GetCharging() is True" after "battery reset" but the device is not
> expected to charge even after reset (Because we are testing the scenario where
> the device is not charging at all)
I need to change how it is detecting that battery updates are resumed.
Now addressing this issue in: 
https://codereview.chromium.org/1180443004/