Trying to move sleep hack to just after page load.

This is another speculative fix since the previous attempt did not
work: https://codereview.chromium.org/94723003.

BUG=281268
TBR=tommi@chromium.org

Review URL: https://codereview.chromium.org/95343003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237800 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237800