TouchInputMapper: Add logs for b/396796958

In this bug, we're seeing test flakes where touches don't get through to
a test activity, and the raw event logs show "syncTouch: pointerCount 0
-> 1" multiple times in a row. To get us some better debugging data,
dump the whole InputReader state as well as the last and next RawStates
when this happens.

Bug: 396796958
Test: enable raw event logs:
      $ adb shell 'stop && setprop log.tag.InputReaderRawEvents DEBUG
                        && start'
      then touch the screen and check the dump appears in the logs.
Test: touch screen and check output of $ adb shell dumpsys input
Test: $ atest --host inputflinger_tests
Test: $ m checkinput
Flag: EXEMPT log only update
Change-Id: I8f1c9ec772971f3e3deefbae94bcae678b1083f4