Introduce VibrationStatsWriter

For writing the event metrics when the custom vibration settings
supports on the device and a custom vibration pattern state has changed
(e.g. saved or playing)

Bug: 434610493
Flag: android.media.audio.enable_ringtone_haptics_customization
Flag: com.android.server.notification.notification_vibration_in_sound_uri
Test: test with statsd_testdrive
Test atest VibrationStatsWriterTest
Test atest NotificationAttentionHelperTest

Change-Id: I96cf69655e5b7f4a54961dca22d87e18d544ff26