Make system layout fill the window properly on expanded desktop mode

This commit fixes e.g. the gap on the bottom of the lock screen
or the gap on the right side of status bar on landscape mode.

Change-Id: If6b4b3aa00b515b055a128f590272da91bd70e23
Revert "Show all widgets on lockscreen"

This reverts commit 8df3f95f5adb92d097b043b3764db8da539b8776.
Bring back lockscreen unlimited widget

Change-Id: Iee7f9ca552850d97247ec2eac7197fc8b1d5da5c