Fix bug when adding an empty editor type in Editor UI.

For both compact editor and full editor, using the method
in RawContactModifier to check if an empty editor type should
be inserted, since that method would check not only overall number,
but also the limit for each specific type.

BUG 22521808

Change-Id: Iefe401f26aec8d8cece4723c0486d3add6732f74