Add blob support to xhr_benchmark.html

Release note: Add blob support to xhr_benchmark.html

R=yhirano@chromium.org

Review URL: https://codereview.appspot.com/13277043

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@782 4ff78f4a-9131-11de-b045-6380ec9940d4
Group benchmark parameters into one dict.

Release note: n/a

R=yhirano@chromium.org

Review URL: https://codereview.appspot.com/13272043

git-svn-id: http://pywebsocket.googlecode.com/svn/trunk@783 4ff78f4a-9131-11de-b045-6380ec9940d4