use hidden prototype chain for new V8 FunctionTemplate feature

 (https://groups.google.com/forum/?fromgroups#!msg/v8-dev/EmOKQOUGqZ0/eJ7b5Yro3EAJ)

In order to avoid "illegal invocation" errors when js calls Ti object's methods ( such as Ti.Media.vibrate() and so on), use setHiddenPrototype(true) for prototype object.