Restore results of startup tests.

In http://src.chromium.org/viewvc/chrome?view=revision&revision=243849
I accidently caused the startup tests to run the default navigate
step. This reverts this, while still making the start with URL tests
run their navigate steps (which they need to do).

BUG=333052
R=dtu@chromium.org

Review URL: https://codereview.chromium.org/134793002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244245 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244245