Remove stale files before extracting, otherwise stale files may survive
Remove stale files before extracting, otherwise stale files may survive

R=chase@chromium.org
BUG=92310
TEST=


Review URL: http://codereview.chromium.org/7607034

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@96214 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build