AOSP/Calendar - update the Calendar version to target P (28) or higher.

Bug: 119500483

Test: manual - Ran the following CTS tests on Pixel phone. Tested the calendar UI.
$ adb shell am instrument -w com.android.calendar.tests

$ ./development/testrunner/runtest.py --path cts/tests/tests/provider/src/android/provider/cts/CalendarTest.java
   android.provider.cts.CalendarTest:................................
   Time: 16.918
   OK (32 tests)

$ ./development/testrunner/runtest.py --path cts/tests/tests/content/src/android/content/cts/AvailableIntentsTest.java
   android.content.cts.AvailableIntentsTest:.................................
   Time: 0.202
   OK (33 tests)

$ ./development/testrunner/runtest.py --path cts/hostsidetests/appsecurity/test-apps/PrivilegedUpdateApp/src/com/android/cts/privilegedupdate/PrivilegedUpdateTest.java
   com.android.cts.privilegedupdate.PrivilegedUpdateTest:...
   Time: 0.204
   OK (3 tests)

$ ./development/testrunner/runtest.py --path cts/tests/tests/permission2/src/android/permission2/cts/ProtectedBroadcastsTest.java
   android.permission2.cts.ProtectedBroadcastsTest:..
   Time: 0.139
   OK (2 tests)

Change-Id: Id3e48f100d685aaf03c2c726b75def4437b980cb