Speculative switch to spawned test server rather than embedded.

Moving the embedded server initialization didn't help. This is the next attempt at resolving our load hangs.

TBR=tommi@chromium.org
BUG=281492

Review URL: https://chromiumcodereview.appspot.com/24261008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@224694 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 224694