Adding battery control API for android.

Adding battery control API for android.

 Also use python __getattr__ to automatically delegate methods from
tools/telemetry/telemetry/core/backends/adb_commands.py to
build/android/pylib/android_commands.py

R=pliard@chromium.org, tonyg@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=261134

[qsr, 2014-04-01 09:15:01]

On 2014/04/01 09:13:09, qsr wrote:

- bulach (OoO)
+ tonyg, pliard

[Philippe, 2014-04-01 09:51:58]

lgtm for changes in build/android/, thanks Benjamin!

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
File build/android/pylib/android_commands.py (right):

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:76: CONTROL_BATTERY_CHARGING_COMMAND = [
Nit: s/COMMAND/COMMANDS?

[tonyg, 2014-04-01 16:13:18]

Some naive questions and comments. Please feel free to discuss, but take my lgtm
in advance to avoid a potential timezone round trip.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
File build/android/pylib/android_commands.py (right):

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:77: {
WDYT about adding a comment listing some example devices that support each dict
in this list? I'm mostly just curious which device has the pm8921.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1839: if
self.FileExistsOnDevice(witness_file):
Maybe we should add an assert that all of the required fields (enable_command,
disable_command) are present in the dict.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1843: def
CanControlBatteryCharging(self):
Is BatteryCharging really the intent of this API? Because one thing is disabling
battery charging, but that isn't that useful to us if the system is still
drawing power from USB. Hopefully the intent is CanControlUsbCharging. If so,
let's rename. If not, I'm curious about the motivation.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1847: command =
self._GetControlBatteryChargingCommand()
Can we cache the enable/disable command in _GetControlBatteryChargingCommand().
That way we don't have to round trip to the device to keep looking if files
exist.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1849: raise Exception('Unable to act on
battery charing.')
s/charing/charging/

https://codereview.chromium.org/218613011/diff/1/tools/telemetry/telemetry/co...
File tools/telemetry/telemetry/core/backends/adb_commands.py (right):

https://codereview.chromium.org/218613011/diff/1/tools/telemetry/telemetry/co...
tools/telemetry/telemetry/core/backends/adb_commands.py:70: """Delegate all
unknown calls to the underlying _adb object."""
Great idea! I recommend adding a TODO to remove this class entirely. Don't
worry, you don't have to put your name by it :)

It seems like anything generally useful here should be moved up.

[qsr, 2014-04-02 09:14:57]

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
File build/android/pylib/android_commands.py (right):

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:76: CONTROL_BATTERY_CHARGING_COMMAND = [
On 2014/04/01 09:51:58, Philippe wrote:
> Nit: s/COMMAND/COMMANDS?

Done.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:77: {
On 2014/04/01 16:13:18, tonyg wrote:
> WDYT about adding a comment listing some example devices that support each
dict
> in this list? I'm mostly just curious which device has the pm8921.

 Done. This one if for the N4 and the only one I have worked with for now.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1839: if
self.FileExistsOnDevice(witness_file):
On 2014/04/01 16:13:18, tonyg wrote:
> Maybe we should add an assert that all of the required fields (enable_command,
> disable_command) are present in the dict.

Done.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1843: def
CanControlBatteryCharging(self):
On 2014/04/01 16:13:18, tonyg wrote:
> Is BatteryCharging really the intent of this API? Because one thing is
disabling
> battery charging, but that isn't that useful to us if the system is still
> drawing power from USB. Hopefully the intent is CanControlUsbCharging. If so,
> let's rename. If not, I'm curious about the motivation.

 You are right. Will rename.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1847: command =
self._GetControlBatteryChargingCommand()
On 2014/04/01 16:13:18, tonyg wrote:
> Can we cache the enable/disable command in
_GetControlBatteryChargingCommand().
> That way we don't have to round trip to the device to keep looking if files
> exist.

Done.

https://codereview.chromium.org/218613011/diff/1/build/android/pylib/android_...
build/android/pylib/android_commands.py:1849: raise Exception('Unable to act on
battery charing.')
On 2014/04/01 16:13:18, tonyg wrote:
> s/charing/charging/

Done.

https://codereview.chromium.org/218613011/diff/1/tools/telemetry/telemetry/co...
File tools/telemetry/telemetry/core/backends/adb_commands.py (right):

https://codereview.chromium.org/218613011/diff/1/tools/telemetry/telemetry/co...
tools/telemetry/telemetry/core/backends/adb_commands.py:70: """Delegate all
unknown calls to the underlying _adb object."""
On 2014/04/01 16:13:18, tonyg wrote:
> Great idea! I recommend adding a TODO to remove this class entirely. Don't
> worry, you don't have to put your name by it :)
> 
> It seems like anything generally useful here should be moved up.

 Did not do it here, because of this comment in the file:

# This is currently a thin wrapper around Chrome Android's
# build scripts, located in chrome/build/android. This file exists mainly to
# deal with locating the module.

 Are you sure we want to remove this? We will have the play with the pythonpath
everywhere we want to use adb.

[qsr, 2014-04-02 09:15:00]

The CQ bit was checked by qsr@chromium.org

[commit-bot: I haz the power, 2014-04-02 09:15:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/qsr@chromium.org/218613011/20001

[qsr, 2014-04-02 16:00:20]

Committed patchset #2 manually as r261134 (presubmit successful).