old_contents: /**
   * Karma Configuration: Base.
   */
  var path = require("path");
  var baseCfg = require("./karma.conf");
  
  // Sauce labs environments.
  var SAUCE_ENVS = {
    "chrome-mac": {
      base: "SauceLabs",
      browserName: "chrome",
      platform: "OS X 10.9"
    },
    "safari-mac": {
      base: "SauceLabs",
      browserName: "safari",
      platform: "OS X 10.9"
    },
    // TODO: Appears to fail conversion tests.
    // "ie9-win7": {
    //   base: "SauceLabs",
    //   browserName: "internet explorer",
    //   platform: "Windows 7",
    //   version: "9"
    // },
    "ie10-win7": {
      base: "SauceLabs",
      browserName: "internet explorer",
      platform: "Windows 7",
      version: "10"
    },
    "ie11-win7": {
      base: "SauceLabs",
      browserName: "internet explorer",
      platform: "Windows 7",
      version: "11"
    }
  };
  
  // Optionally filter browsers from environment or "all browsers"
  var BROWSERS = (process.env.BROWSERS || "")
    .split(",")
    .filter(function (x) { return x; });
  if (!BROWSERS.length) {
    BROWSERS = Object.keys(SAUCE_ENVS);
  }
  
  // SauceLabs tag.
  var SAUCE_BRANCH = process.env.TRAVIS_BRANCH || "local";
  var SAUCE_TAG = process.env.SAUCE_USERNAME + "@" + SAUCE_BRANCH;
  
  module.exports = function(config) {
    baseCfg(config);
    config.set({
      reporters: ["spec", "saucelabs"],
      sauceLabs: {
        testName: "full-stack-testing - Frontend Unit Tests",
        tags: [SAUCE_TAG],
        public: "public"
      },
      // Timeouts: Allow "n" minutes before saying "good enough". See also:
      // https://github.com/angular/angular.js/blob/master/karma-shared.conf.js
      captureTimeout: 0, // Pass through to SL.
      customLaunchers: SAUCE_ENVS,
      browsers: BROWSERS
    });
  };
  
new_contents: /**
   * Karma Configuration: Base.
   */
  var path = require("path");
  var baseCfg = require("./karma.conf");
  
  // Sauce labs environments.
  //
  // These are custom definitions that we can later invoke specifically on the
  // command line with `--browsers KEY1,KEY2`, etc.
  var SAUCE_ENVS = {
    "sl-chrome-mac": {
      base: "SauceLabs",
      browserName: "chrome",
      platform: "OS X 10.9"
    },
    "sl-safari-mac": {
      base: "SauceLabs",
      browserName: "safari",
      platform: "OS X 10.9"
    },
    // TODO: Appears to fail conversion tests.
    // "sl-ie9-win7": {
    //   base: "SauceLabs",
    //   browserName: "internet explorer",
    //   platform: "Windows 7",
    //   version: "9"
    // },
    "sl-ie10-win7": {
      base: "SauceLabs",
      browserName: "internet explorer",
      platform: "Windows 7",
      version: "10"
    },
    "sl-ie11-win7": {
      base: "SauceLabs",
      browserName: "internet explorer",
      platform: "Windows 7",
      version: "11"
    }
  };
  
  // SauceLabs tag.
  var SAUCE_BRANCH = process.env.TRAVIS_BRANCH || "local";
  var SAUCE_TAG = process.env.SAUCE_USERNAME + "@" + SAUCE_BRANCH;
  
  module.exports = function(config) {
    baseCfg(config);
    config.set({
      reporters: ["spec", "saucelabs"],
      sauceLabs: {
        testName: "full-stack-testing - Frontend Unit Tests",
        tags: [SAUCE_TAG],
        public: "public"
      },
      // Timeouts: Allow "n" minutes before saying "good enough". See also:
      // https://github.com/angular/angular.js/blob/master/karma-shared.conf.js
      captureTimeout: 0, // Pass through to SL.
      customLaunchers: SAUCE_ENVS,
      browsers: Object.keys(SAUCE_ENVS)
    });
  };
  
subject: Remove BROWSERS env var in favor of first class --browsers