Make Android Mojo Runner respect command line apps.

Make Android Mojo Runner respect command line apps.

Make Mandoline always run the mojo:window_manager.
(afaik we don't want to specify other command line apps)
Make Mojo Runner run the command line app (fallback on WM).
(The Android impl wasn't respecting the command line app)
Consolidate on Context::RunCommandLineApplication helper.

BUG=486220
TEST=Android mojo shell and apptest runner can run non-WM apps (eg. apptests).
R=sky@chromium.org

Committed: https://crrev.com/1a4bbd1c973adbeeb9c9b4db061186a89fabbf0d
Cr-Commit-Position: refs/heads/master@{#329970}

[msw, 2015-05-14 22:48:33]

msw@chromium.org changed reviewers:
+ sky@chromium.org

[msw, 2015-05-14 22:50:04]

Hey Scott, please take a look; thanks!

[sky, 2015-05-14 23:02:27]

LGTM

[msw, 2015-05-14 23:03:12]

The CQ bit was checked by msw@chromium.org

[commit-bot: I haz the power, 2015-05-14 23:04:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1134713003/100001

[commit-bot: I haz the power, 2015-05-14 23:17:34]

Committed patchset #6 (id:100001)

[commit-bot: I haz the power, 2015-05-14 23:18:30]

Patchset 6 (id:??) landed as
https://crrev.com/1a4bbd1c973adbeeb9c9b4db061186a89fabbf0d
Cr-Commit-Position: refs/heads/master@{#329970}