Files.app: Fix file name in the grid view.

The utility method to render filenames requires Entry as an argument but the
file grid passes string. This CL fix the problem.

BUG=302891
TEST=manually

Review URL: https://codereview.chromium.org/25356003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226695 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 226695