Merge change 20706

* changes:
  Improve Browser performance by 1-2%. To address domain sanity bug, http://b/issue?id=1022797, we decoded/encoded the url for each request. As the url can be long, getBytes() and String.init are taking 1.5% in nytimes.com and 2.4% in cnn.com. By doing a simple URL encoding test, we can shave 1-2 secs thread time during loading.