Update V8 to version 3.23.7.

TBR=danno@chromium.org
BUG=

Review URL: https://codereview.chromium.org/64093007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235990 0039d316-1c4b-4281-b951-d872f2087c98
Remove policy_constants.h includes.

Facilitates the move of chrome/browser/policy into a layered
component. policy_constants.h cannot be included from there.
This CL removes some extraneous uses of this include and
refactors test code to avoid relying on hardcoded policy names.

BUG=271392

Review URL: https://codereview.chromium.org/68103025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235991 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235992 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 235992