Hides the "Remove thumbnails" link when the most visited intro is shown.
Hides the "Remove thumbnails" link when the most visited intro is shown.

BUG=None

TEST=With an empty history, open a new tab. The NTP should not show the link
to "Remove thumbnails". Browse 3 different sites and open a new tab again. The
link "Remove thumbnails" should now be visible.


Review URL: http://codereview.chromium.org/115787

git-svn-id: http://src.chromium.org/svn/trunk/src@16994 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 160694b5d4dd79feb53442168955a69f2c4a11bf
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser