Revert r229540 "Changes to reinitialize the appcache system if/when DiskCache initialization fails."
Breaks AppCacheStorageImplTest.Reinitalize

TBR=michaeln

Review URL: https://codereview.chromium.org/30523002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229544 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229544