Changes to support Android Things N on Cast master

Test: Built and Run with Android N(on Cast Master) changes (Cast + setup) on the AT1
Bug: 118437285
Change-Id: Iff72a2a2d8eabda619940a256bab1b23daf00c26
Reviewed-on: https://chromium-review.googlesource.com/c/1331579
Commit-Queue: Elvin L <elvin@chromium.org>
Reviewed-by: Luke Halliwell <halliwell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608393}

• chromecast/BUILD.gn[diff]
• chromecast/base/BUILD.gn[diff]
• chromecast/base/cast_sys_info_android_factory.cc[diff]
• chromecast/browser/BUILD.gn[diff]
• chromecast/browser/android/BUILD.gn[diff]
• chromecast/chromecast.gni[diff]
• chromecast/media/cma/backend/android/java/src/org/chromium/chromecast/cma/backend/android/VolumeMap.java[diff]