How to run benchmarks for Media Router

1. Run the following command to find all the available browsers:

./chrome/test/media_router/telemetry/run_benchmark --browser list

Let <browser> be one of the results.

2. Run the following command to get benchmarks for media router dialog latency:

./chrome/test/media_router/telemetry/run_benchmark --browser=<browser> \
    media_router.cpu_memory

The results will be in <chromium src folder>/chrome/test/media_router/telemetry/results.html