SystemUI: Fix wrong behavior of recents pie.

Call preloadRecentTasksList when user moves over
recents pie.

Change-Id: Ic62343cb6ae9c5ab8bb90bf6eca4fb2d13493cac
Merge "SystemUI: Fix wrong behavior of recents pie." into cm-10.2
Merge branch 'cm-10.2' of git://github.com/CyanogenMod/android_frameworks_base into cm-10.2