On mobile data the single default streaming quality either burns
through the user's data plan or permanently caps quality at home.
Playback start now applies a dedicated cellular default when the
device is on a cellular-only connection, read from the app's existing
single connectivity subscription. The new setting defaults to
following the general default, ships in Settings > Playback for
phones/tablets only, and explicit per-play quality picks still win.
'Metered connection' had been spelled out independently in the offline
provider, the download WiFi-only gate and the sync-rule cooldown.
Rather than add a fourth copy, all four now share
ConnectivityLinkType. Network *presence* is deliberately left alone:
its callers disagree on whether an empty snapshot counts as
connected, so folding that in would change behavior.
showSelectionDialog now returns the picked DialogOption instead of its
raw value so the tile's null-valued 'Same as Default Quality' option
stays distinguishable from dismissing the dialog.
close#2147
edde746
9ac8002b53