I needed clarification about the same topic. Based on the information in Publication 17, it appears that you would still be required to file because the gross income that is used to determine if you are over the filing threshold includes your gross self-employment income, before expenses are deducted.
From the publication:
Self-employed individuals. If you are self-employed, your gross income includes the amount on line 7 of Schedule C (Form 1040), Profit or Loss From Business; and line 9 of Schedule F (Form 1040), Profit or Loss From Farming. See Self-Employed Persons, later, for more information about your filing requirements.
