[benchmark.html] Use bind to build test runner closures.
[benchmark.html] Use bind to build test runner closures.

R=yhirano@chromium.org

Review URL: https://codereview.appspot.com/106180044
google/pywebsocket,googlearchive/pywebsocket,google/pywebsocket,GoogleChromeLabs/pywebsocket3,GoogleChromeLabs/pywebsocket3,GoogleChromeLabs/pywebsocket3,googlearchive/pywebsocket,google/pywebsocket,googlearchive/pywebsocket