Fix handling of escape key

Authored by Pppery on May 18 2017, 1:25 AM.

Description

Fix handling of escape key

Previously, pressing ESC aborted the dragging of the slider, but this
was broken by I64cca7a7547310bee64ad95f500b722c362bbb45, which refactored
uses of a variable that was previously a closure into two separate functions.

Bug: T140965
Change-Id: I6b7bc383128d8c7d99da469706bff881f1329cd9

Details