TouchpadInputMapper: add timer provider

Adding a timer provider allows the Gestures library to perform some
asynchronous tasks, including ones which improve tap-to-click detection.

Bug: 297192727
Test: set the
      persist.device_config.aconfig_flags.input.com.android.input.flags.enable_gestures_library_timer_provider
      sysprop to true, restart, then make fast tap-to-click gestures
      (where the finger is contacting for fewer than 3 frames) on the
      touchpad, and check they're reported immediately
Change-Id: Ib9b8dacc71c88b6fd47bdd747f90ef6a44b37cc4