Enable incremental linking for browser_tests on Windows.

This is based on scottmg's https://codereview.chromium.org/25377002/.

BUG=308773
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/82713004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236855 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236855