Fixing issue for developer chrome launch.
Issue was related to how CHROME_VERSION environment variable gets set.

BUG=
R=cpu

Review URL: https://codereview.chromium.org/183663005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254162 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254162