commit 1241e61a4568bfda63c731fba78286898eaba008
author Hyunyoung Song <hyunyoungs@google.com> Tue May 15 21:46:51 2018 -0700
committer Hyunyoung Song <hyunyoungs@google.com> Wed May 16 11:26:35 2018 -0700
tree 6b5d426cb6f1a9ccdb40197e7ad8f839d8ee1def
parent d9a1337b40fcb1041bba48cd59d7f358f5b7895f

Improve Task user event logging
Bug: 79539824
Bug: 79541772

(1) Added page index of the TASK that is being launched
(2) Covers all three cases of task launch (tap, swipe down, quick scrub)
UserEvent: action:FLING direction=DOWN
UserEvent:  Source child:TASK, packageHash=-1598699687, componentHash=1952702153, pageIdx=0

UserEvent: action:DRAGDROP
UserEvent:  Source child:TASK, packageHash=-744307622, componentHash=-515832044, pageIdx=4

(3) Avoid double logging (When onStop is called, it is not logged if
the cause of onStop is APP or TASK launch)

Change-Id: Ic5db7d6a640d43bfb5cd667b49e37dd0ed127d5c