Mark svg-in-object-placeholder-height tests as timing out

Mark new svg-in-object-placeholder-height tests as timing out.

BUG=308992
TBR=davve@opera.com

Review URL: https://codereview.chromium.org/243393004

git-svn-id: svn://svn.chromium.org/blink/trunk@171975 bbb929c8-8fbe-4397-9dbb-9b2b20218538