Introduce .DEPS.git file to support full git checkouts

This is the result of running deps2git.py -d DEPS -o .DEPS.git -s -c /tmp

BUG=none
R=jkummerow@chromium.org, machenbach@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/246633009

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20907 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Harden DefineOrRedefineDataProperty.

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/240973002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20908 ce2b1a6d-e550-0410-aec6-3dcde31c8c00