fixes issue with appcache db coruption... finally found a solution!!!

https://code.google.com/p/chromium/issues/detail?can=2&start=0&num=100&q=&colspec=ID%20Pri%20M%20Iteration%20ReleaseBlock%20Cr%20Status%20Owner%20Summary%20OS%20Modified&groupby=&sort=&id=258191
Merge branch 'master' of github.com:tesera/tractor-beam