Revert "Add new APIs to provide a hint to the AccessibilityServi..."

Revert submission 21320459-chunkulin-a11yNode-setTouchPassthrough

Reason for revert: TB is unsure on specific UX for using this, so removing as a FW API for Android U with plans to reland & prototype in AndroidX for now
Bug: 274703184

Reverted changes: /q/submissionid:21320459-chunkulin-a11yNode-setTouchPassthrough

Change-Id: Iedb2945b64e6cb84e83f8f9e3111517d6c55bf67