Disk cache: Remove some dead code.
Disk cache: Remove some dead code.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/598074

git-svn-id: http://src.chromium.org/svn/trunk/src@38818 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 8b7dabdc4b33295baa2bc06c74f89cf7a0713d26
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