a11y: Add test coverage for autoclick click type

Override super.onMotionEvent() with a fake method to capture the click events
sent from autoclick.

Bug: b/399948761
Test: AutoclickTypePanelTest
Flag: com.android.server.accessibility.enable_autoclick_indicator
Change-Id: Idb408103a9831971f0b878d264fd21f710bccfa5