Implement WebFileSystemImpl::directoryName.  This is needed for directory upload (including webkit layout tests).
Implement WebFileSystemImpl::directoryName.  This is needed for directory upload (including webkit layout tests).

BUG=41762
TEST=webkit layout test fast/forms/input-file-directory-upload.html

Review URL: http://codereview.chromium.org/2847056

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@52829 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser