Handle the null folder_name case.
Handle the null folder_name case.

Submitting the code for yukawa.  See http://codereview.chromium.org/7703004/
Review URL: http://codereview.chromium.org/7739004

git-svn-id: e7e1075985beda50ea81ac4472467b4f6e91fc78@1026 78cadc50-ecff-11dd-a971-7dbc132099af

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