Inactive calendar widget should be closed

If 2 calendar widgets are opened, widget "To:" is always on the
top of widget "From:" despite of what of text field is active.
As result I can't fully choose "From:" date if "To:" widget is
also opened.

Change-Id: I72878120cff1db2aa42a7f6843e61d9252e3106b
Closes-bug:#1307541
Merge "Inactive calendar widget should be closed"