Change EXTRA_TIME_PREF_24_HOUR_FORMAT from boolean to int

... on Intent.ACTION_TIME_CHANGED.

This is to better represent the possible settings values for
the "use 24 hour format" setting. These are "12" (use 12 hour
formatting), "24" (use 24 hour formatting), unset
(use locale default formatting).

The EXTRA_TIME_PREF_24_HOUR_FORMAT for the ACTION_TIME_CHANGED
is now an int, not a boolean. 0 means "12", 1 means "24" and
2 means "use locale default". This is not a backwards compatible
change but the EXTRA_TIME_PREF_24_HOUR_FORMAT is not public
and so should only affect platform code that generates or
consumes the intent like settings code.

There are associated changes to Settings code to update the source
of the Intent.

The related underlying code that is triggered in response to the
intent and previously assumed a boolean now takes a Boolean.

Other changes:

The ActivityManagerService now only sends a binder notification
to running services if the EXTRA_TIME_PREF_24_HOUR_FORMAT
is present. There is an example of ACTION_TIME_CHANGED
being sent from the platform (AlarmManagerService, when the system
clock is noticed to have changed independently of the RTC) that
does not set the extra and would previously have misinterpreted
to mean "user wants 12 hour formatting", which would have been a
bug.

i.e. the code from ActivityManagerService that would interpret the
missing extra as false:

final int is24Hour =
        intent.getBooleanExtra(
                Intent.EXTRA_TIME_PREF_24_HOUR_FORMAT, false) ? 1 : 0;

Some methods and constants have be renamed to better reflect their
use.

Bug: 32761619
Bug: 32933009
Test: Manual testing
Change-Id: Ie7e9c62ce65e7e3a056b2751b45fe6cb9de86498