[Cast, Android, PresentationAPI] Show play/pause button when the presentation supports media comman…

[Cast, Android, PresentationAPI] Show play/pause button when the presentation supports media commands.

Add RemoteMediaPlayer to the CastRouteController.
Notify it of the media namespace messages.
Use it to handle play/pause from the controls.

BUG=541629
Committed: https://crrev.com/00f44574c776d9c4850c42e36c4eae8d60d9cb98
Cr-Commit-Position: refs/heads/master@{#357131}

[whywhat, 2015-10-29 14:02:19]

avayvod@chromium.org changed reviewers:
+ mlamouri@chromium.org

[whywhat, 2015-10-29 14:02:20]

PTaL

[whywhat, 2015-10-29 19:15:48]

Rebased

[mlamouri (slow - plz ping), 2015-10-30 11:37:59]

The CQ bit was checked by mlamouri@chromium.org

[mlamouri (slow - plz ping), 2015-10-30 11:38:00]

lgtm

[commit-bot: I haz the power, 2015-10-30 11:38:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1412293004/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1412293004/60001

[whywhat, 2015-10-30 16:50:59]

The CQ bit was checked by avayvod@chromium.org

[whywhat, 2015-10-30 16:50:59]

The patchset sent to the CQ was uploaded after l-g-t-m from
mlamouri@chromium.org
Link to the patchset: https://codereview.chromium.org/1412293004/#ps80001
(title: "Remove "Casting to" from the notification title.")

[commit-bot: I haz the power, 2015-10-30 16:52:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1412293004/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1412293004/80001

[commit-bot: I haz the power, 2015-10-30 18:26:36]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2015-10-30 18:28:00]

Patchset 5 (id:??) landed as
https://crrev.com/00f44574c776d9c4850c42e36c4eae8d60d9cb98
Cr-Commit-Position: refs/heads/master@{#357131}