[Android] Make BatteryStatusManagerTest compilable on M

[Android] Make BatteryStatusManagerTest compilable on M

BatteryStatusManagerTest does not compile on M because of the
changes to the BatteryManager class. This patch introduces
AndroidBatteryManagerWrapper to make the system battery manager
testable on M.

BUG=488690
Committed: https://crrev.com/2f08ccf895d5c96019da0cd6cfea23cb6b34c18f
Cr-Commit-Position: refs/heads/master@{#330723}

[timvolodine, 2015-05-18 14:45:13]

timvolodine@chromium.org changed reviewers:
+ yfriedman@chromium.org

[Yaron, 2015-05-19 13:55:06]

lgtm

thanks

[timvolodine, 2015-05-19 17:24:19]

The CQ bit was checked by timvolodine@chromium.org

[commit-bot: I haz the power, 2015-05-19 17:25:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1130253012/20001

[commit-bot: I haz the power, 2015-05-19 18:14:43]

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

[commit-bot: I haz the power, 2015-05-19 18:14:44]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[timvolodine, 2015-05-20 10:39:36]

The CQ bit was checked by timvolodine@chromium.org

[timvolodine, 2015-05-20 10:39:37]

The patchset sent to the CQ was uploaded after l-g-t-m from
yfriedman@chromium.org
Link to the patchset: https://codereview.chromium.org/1130253012/#ps40001
(title: "remove unused mAndroidBatteryManager field")

[commit-bot: I haz the power, 2015-05-20 10:39:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1130253012/40001

[commit-bot: I haz the power, 2015-05-20 10:43:51]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-05-20 10:44:49]

Patchset 3 (id:??) landed as
https://crrev.com/2f08ccf895d5c96019da0cd6cfea23cb6b34c18f
Cr-Commit-Position: refs/heads/master@{#330723}