Exclude chrome_browser_main.cc's printf in PRESUBMIT.py.

The printf in that file is legitimate, so it shouldn't
trigger the warning.

BUG=none
NOTRY=true

Review URL: https://codereview.chromium.org/103133002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238522 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 238522