[MediaRouter, Android] Rebase the controller dialog fragment.

[MediaRouter, Android] Rebase the controller dialog fragment.

MediaRouteControllerDialogManager.Fragment inherits from
BaseMediaRouteDialogManager.Fragment which inherits from
MediaRouteChooserDialogFragment. I changed the former to inherit
directly from the MediaRouteControllerDialogFragment and merged the base
dialog fragment logic with both Chrome's custom fragment classes.

In the essence, the rebasing is needed so that two final subclasses could
inherit from the right MediaRouteXXXDialogFragment (Chooser and Controller)
- that's the only behavioral change that fixes the problem.

BUG=667269
TEST=manual on any cast-enabled mobile-friendly website.
TBR=mlamouri@chromium.org

Review-Url: https://codereview.chromium.org/2523413002
Cr-Commit-Position: refs/heads/master@{#434528}
(cherry picked from commit cebca8e4a6d6e86016a8b26812e74d706d2e8a16)

[whywhat, 2016-11-30 17:21:56]

Committed patchset #1 (id:1) to pending queue manually as
8bad0745b1723787fcc4956791598669da02ff55.