Add support for Content-Disposition when save link

Content-Disposition isn't used when downloading an
item by long-click the link. It'll result in different
file name if the item is downloaded by clicking the link
or if it's downloaded by long-click the link and select
Save link if the HTTP response includes the Content-Disposition
header with the filename attribute

Change-Id: I7eacfd1128da261e0674bbdc3064208a82e46ab3
1 file changed