Polish transfer starting window across more than two activities.

Previous we do not allow to transfer starting window if the orientation
between activities are mismatch, which would make the starting window
leave in original activity. But if there are more than 3 activities
launching during a launch sequence, and the initial starting window
wasn't transfer to 2nd activity, then we can transfer the starting
window from initial activity to the 3rd launched activity if the 2nd
activity isn't report drawn because the 2nd activity has not shows on
screen. But if the window of 2nd activity is drawn, do not transfer the
starting window anymore.
Also fix a flicker after transfer starting window that the starting
window could be removed when transition complete, before the first
window drawn on the activity.

Flag: EXEMPT bugfix
Bug: 379567320
Test: Launch activities in orientation(UNDEFINED -> LANDSCAPE ->
UNDEFINED), if the second activity never show on screen, then the
starting window should transfer to last activity. Otherwise the
starting window should remain in the first activity.

Change-Id: Ic095ccf4139ac1818146b2203a776c13b807cbcc