Streams arrays and getFirst()

[Jose]

To use arrays as inputs for lambda pipelines I'm currentely using:

                 Arrays.asList(myArray).filter(...).map(...)

I'm also testing to refractor some methods in my code 

T  foo(List list){}                  to     T foo(Iterable iter)

If the foo() body needs the first element of the iterable,  I can provide it
with the extension method:

                                               
                                                          Iterable.
getFirst()

However I thik that this method could do better in the array case, because
now it is not checking if the passed argument is a List. 

For example, another method in the class

                                                        Iterable.count()

already check for the argument being a Collection and then returns its size,
no need to compute it. 

Would you mind to include the List check in getFirst()?