This fixes a few issues with the "Mobile network" preference that shows
on the Network & internet page:
-The pref should not be available at all if the device is wifi-only.
-The pref should be disabled in airplane mode.
-If eSIM support is disabled, we need to disable entry points for adding
a new eSIM subscription (the summary and click handler in single-SIM
mode with no physical SIM, and the 'add' button in dual-SIM mode).
Bug: 116349402
Test: make RunSettingsRoboTests
Change-Id: Ic6fe426e9f890d80b399d48a2c9984d4d8b02a10
On the Network & internet page, we have a "Mobile network" pref that in
single-SIM mode leads to a detail page for the current SIM. In multi-SIM
mode it has more complicated behavior (leading either to details about
the current subscription if there is only one, or a list of
subscriptions if more than one).
One of the things we wanted to add was a shortcut to add another eSIM
subscription. So this CL adds a plus button control on the right of the
preference which leads to a flow to add another mobile subscription via
the eSIM manager.
Bug: 116349402
Test: make RunSettingsRoboTests
Change-Id: I38e0031e3bd603e93c45dcb4557750e7bc1b8b5a
