[Android] Add base_junit_tests to VALID_TESTS in bb_device_steps.

[Android] Add base_junit_tests to VALID_TESTS in bb_device_steps.

Fixes https://codereview.chromium.org/1127153004/

BUG=

Committed: https://crrev.com/71a2498cb90f95fc810f2945b9a81288ecccae55
Cr-Commit-Position: refs/heads/master@{#329220}

[jbudorick, 2015-05-11 16:00:14]

jbudorick@chromium.org changed reviewers:
+ dgn@chromium.org, perezju@chromium.org

[perezju, 2015-05-11 16:39:17]

lgtm

[jbudorick, 2015-05-11 18:10:46]

The CQ bit was checked by jbudorick@chromium.org

[jbudorick, 2015-05-11 18:10:46]

The patchset sent to the CQ was uploaded after l-g-t-m from perezju@chromium.org
Link to the patchset: https://codereview.chromium.org/1135053003/#ps20001
(title: "rebase")

[commit-bot: I haz the power, 2015-05-11 18:11:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1135053003/20001

[commit-bot: I haz the power, 2015-05-11 18:41:02]

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

[commit-bot: I haz the power, 2015-05-11 18:41:03]

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

[jbudorick, 2015-05-11 18:43:05]

The CQ bit was checked by jbudorick@chromium.org

[commit-bot: I haz the power, 2015-05-11 18:43:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1135053003/20001

[commit-bot: I haz the power, 2015-05-11 19:13:04]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-05-11 19:14:00]

Patchset 2 (id:??) landed as
https://crrev.com/71a2498cb90f95fc810f2945b9a81288ecccae55
Cr-Commit-Position: refs/heads/master@{#329220}