TextView: start drag and drop when dragging selection by mouse.
TextView: start drag and drop when dragging selection by mouse.

Previously, drag and drop is started only when a long click is detected.
With this CL, drag and drop is started on drag when a mouse is used.

Bug: 19544351
Change-Id: If81f9edc6fcff5f7a810b2165c058aa36fb6caad

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base