IndexedDB: Re-animate some undead code
A few overrides that just added NOTREACHED() were not renamed during
the Blink->Chromium code migration, and not caught because they were
missing the OVERRIDE directive. This was caught by a dead-code
detector. Add OVERRIDE and rename them correctly. Also rename trivial
Value() accessor to value() to matching coding style.
R=alecflett@chromium.org
Review URL: https://codereview.chromium.org/
107223005
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239263 0039d316-1c4b-4281-b951-d872f2087c98