Popover is not positioned correctly when viewport property is used

[amiklosi]

You can see the issue in this fiddle: http://jsfiddle.net/699rsu57/

The fix is actually quite easy for this:
In tooltip.js getViewportAdjustedDelta function the line

} else if (rightEdgeOffset > viewportDimensions.width) { // right overflow

should read

} else if (rightEdgeOffset > viewportDimensions.right) { // right overflow

[klakshman318]

Try like this 👍

[fat]

in v4 we're going to rewrite the position engine/use a 3rd party one.

meanwhile - i'm happy to review a pr if you or someone else wants to make this change