Revert 217570 "Undo band-aid which was ignoring wrong SessionSto..."

> Undo band-aid which was ignoring wrong SessionStorage association
>
> The baind-aid was r143761. Now that crbug.com/138152 and
> crbug.com/269449 are fixed, we can hopefully do without.
>
> BUG=269449
> R=marja@chromium.org
>
> Review URL: https://chromiumcodereview.appspot.com/23184002

BUG=325378
R=jochen@chromium.org
TBR=jochen@chromium.org

Review URL: https://codereview.chromium.org/105103006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240394 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240394