am e02e8b9c: Merge change 27315 into eclair

Merge commit 'e02e8b9c11231d99aacd5fda31042168650edd49' into eclair-plus-aosp

* commit 'e02e8b9c11231d99aacd5fda31042168650edd49':
  Reset mPreventDrag at touch_down.