Add 1-day sync stats in syncmanager dumpsys.

The stats currently shown in sync manager dumpsys is the total *since wipe* so
they're usually pretty much useless.

So let's add "today" and "yesterday" stats too.

- Also add "# failures" and "# cancels".
- Also split up SERVER to OTHER and FEED (i.e. subscribedfeeds).

Bug: 76035392
Test: Boot, run some sync, then do "cmd content reset-today-stats"
- Also tested with actually setting the clock to 23:59 and wait
- Check the result with "dumpsys content".

Sample output:
=======================================================================
Authority                                           Syncable  Enabled  Stats  Loc  Poll  Per  Feed  User  Othr  Tot  Fail  Can  Time  Last Sync            Backoff
------------------------------------------------------------------------------------------------------------------------------------------------------------------
com.android.calendar                                1         true     Total  0    0     0    1     0     7     8    0     2    8s    FEED SUCCESS
                                                                       Today                  1           5     6               7s    2018-04-12 15:21:24
                                                                       Yestr                                                    0s
com.android.chrome                                  0         false    Total  0    0     0    0     0     0     0    0     0    0s
                                                                       Today                                                    0s

Change-Id: Id0ea42435a9f759e47d4b9490292759270f8e9a5