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: de016e52bd170d2d4f2344f9bf92d50478b649e0@21335 0039d316-1c4b-4281-b951-d872f2087c98

adobe/chromium,adobe/chromium,adobe/chromium,Crystalnix/house-of-life-chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,yitian134/chromium,ropik/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,yitian134/chromium,gavinp/chromium,adobe/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,adobe/chromium,yitian134/chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,ropik/chromium,adobe/chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,adobe/chromium,gavinp/chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,gavinp/chromium,ropik/chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,yitian134/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,gavinp/chromium,ropik/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,ropik/chromium,gavinp/chromium