Fixing duplicate status bars in unfolded mode

The issue was caused by incorrect alpha calculation - getLockscreenShadeDragProgress should account for special case of going directly to expanded QS on lockscreen, when "dragProgress" is not updated.
Also putting keyguard status bar refresh close to split shade header refresh, otherwise keyguard status bar alpha wouldn't update often enough and animation would look like it's stuck.

Bug: 212544026
Test: in folded mode lockscreen pull down shade from the top to expanded QS -> unfold and see only one status bar
Change-Id: I3e8c66589270469cfc1484963d0a53c7273d07c1