node.cloneNode() should clone the value of file selected

when input element of type file with a selected file is cloned, the cloned node should
also have the same file as selected.
HTML specification states:
http://www.whatwg.org/specs/web-apps/current-work/multipage/the-input-element.html
"The cloning steps for input elements must propagate the value, dirty value
flag, checkedness, and dirty checkedness flag from the node being cloned to the
copy."

The value for the input element of type fileupload is the filename.

Behaviours in major Browser:
Firefox- clones filename
Safari, IE & Opera- do not Clone filename 

BUG=71536
TEST=fast/forms/file/input-file-element-clone.html

Review URL: https://codereview.chromium.org/267713006

git-svn-id: svn://svn.chromium.org/blink/trunk@173626 bbb929c8-8fbe-4397-9dbb-9b2b20218538