Exclude uneeded strings from chrome and chromium strings.

BUG=326023

Review URL: https://codereview.chromium.org/174173002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252405 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252405