Skip webkit tests in debug that are very slow.

Duration for each is between 14 s and 160 s.

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/18034017

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15374 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

test/webkit/webkit.status

@@ -24,3 +24,9 @@
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# Too slow in debug mode.
+dfg-int-overflow-in-loop: PASS, SKIP if $mode == debug
+dfg-double-vote-fuzz: PASS, SKIP if $mode == debug
+reentrant-caching: PASS, SKIP if $mode == debug
+sort-large-array: PASS, SKIP if $mode == debug