Update reliability_tests for Chromium waterfall.
Update reliability_tests for Chromium waterfall.

- Ignore no results since test bots visit erroneous URLs and fail all the time.
- Add option to pass in dashboard URL.

Review URL: https://chromiumcodereview.appspot.com/12038023

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@178333 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build