This reverts commit 28058.

BUG=24081
TEST=gclient sync without --force is not working anymore.
TBR=dpranke

Review URL: http://codereview.chromium.org/269006

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@28271 0039d316-1c4b-4281-b951-d872f2087c98