var coord = new google.maps.LatLng({lat: 0, lng: 0});
coord.lat()//gives NaN, should give 0
coord.lng()//gives NaN, should give 0

Using it as 
coord = new google.maps.LatLng(0, 0) 
works fine, both coord.lat() and coord.lng() gives 0 as expected.

Bug is in function google.maps.LatLng, the conditional 
if (a && (a.lat || a.lng)) is WRONG, 
it should check for 
if (a && (!isNaN(a.lat) || !isNaN(a.lng)))
or similar.