Our existing precision is milliseconds so we want to stick with that for
Instants. If we want to increase the precision globally after that we can do so
all in one go post-migration, but for now, it would be a bad thing to have mixed
precision going on just depending on whether a class happens to be migrated yet
or not.
This PR also migrates all existing DateTime.nowUtc() calls to use the Clock
interface, so that when they are migrated they will get the benefit of this
precision-setting as well.
BUG= http://b/496985355
java.time has been around since Java 8 and was based on joda DateTime, so this
is an overdue migration. We're migrating specifically to Instant in most places
rather than ZonedDateTime because we were always using DateTimes in UTC to
reference a specific instant, which is exactly what Instants are
for. ZonedDateTime set to UTC may still be useful in some places that are heavy
on date math (especially in tests).
There is a lot more work to be done after this, but I wanted to put together a
manual PR showing my overall approach for how to do the migration that I can
then hopefully follow along with AI to continue making these changes throughout
the codebase. The basic approach is to migrate a small number of methods at a
time, marking the old methods as @Deprecated when possible (not always possible
because of @InlineMe restrictions). This PR doesn't yet migrate any DateTime
fields in the model classes, so that's the one remaining type of refactor to
figure out after this. We won't be changing how any of the data is actually
stored in the database.
BUG= http://b/496985355
* Break circular dependency between core and util
Created a new :common project and moved a minimum
number of classes to break the circular dependency
between the two projects. This gets rid of the
gradle lint dependency warnings.
Also separated api classes and testing helpers into
separate source sets in :common so that testing
classes may be restricted to test configurations.
