Change global transcode enable toggle preference to global disable
toggle preference. Change app slection for skipping transcode to
app selection for enabling transcode, by default transcoding would be
disabled for all apps.
Test: Manual, Roboelectric unit tests
Change-Id: I44f4d1b24fac70a4560e8b3a12d505bd2da26f20
This screen would be used to enable/disable transcoding for all apps, and select a list of apps to be skipped from transcoding.
UI screenshot: https://screenshot.googleplex.com/4bpbZdM6vbhdw5u
Design doc reference for native transcoding: go/seamless-transcoding
Test: Manual
Bug: 169547037
Change-Id: I7cf72131560b99728083838bf0dad400bb5cb4a9