Teach window.location.href setter to handle relative urls.

Also fixed display of text in touch-demo.sky

R=ianh@google.com

Review URL: https://codereview.chromium.org/1059743004

examples/raw/touch-demo.sky

@@ -12,6 +12,7 @@ dot {
 }
 
 log {
+    display: paragraph;
     margin-top: 50px;
 }
 </style>