Fix memory leak in FileDataSource FileDataSource broke the linux valgrind build because the callback for read was not deleted.
Fix memory leak in FileDataSource
FileDataSource broke the linux valgrind build because the callback
for read was not deleted.

TBR=scherkus

Review URL: http://codereview.chromium.org/159234

git-svn-id: http://src.chromium.org/svn/trunk/src@21335 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 0ca60e6a43448d06637d9bd6ff5aca1d95ceeebd
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser