Add codegen test for equality.

pkg/dev_compiler/karma.conf.js

 // Karma configuration
 // Generated on Mon Apr 20 2015 06:33:20 GMT-0700 (PDT)
 
 module.exports = function(config) {
   var configuration = {
 
     // base path that will be used to resolve all patterns (eg. files, exclude)
     basePath: '',
 
     // frameworks to use
     // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
     frameworks: ['mocha', 'requirejs', 'chai'],
 
     // list of files / patterns to load in the browser
     files: [
       {pattern: 'lib/js/amd/dart_sdk.js', included: false},
+      {pattern: 'gen/codegen_output/*.js', included: false},
       {pattern: 'gen/codegen_output/pkg/*.js', included: false},
       {pattern: 'gen/codegen_output/language/**/*.js', included: false},
       {pattern: 'gen/codegen_output/corelib/**/*.js', included: false},
       {pattern: 'gen/codegen_output/lib/**/*.js', included: false},
       {pattern: 'gen/codegen_tests/lib/**/*.txt', included: false},
       {pattern: 'test/browser/*.js', included: false},
-      {pattern: 'node_modules/is_js/*.js', included: false},      
+      {pattern: 'node_modules/is_js/*.js', included: false},
       'test-main.js',
     ],
 
     // list of files to exclude
     exclude: [],
 
     // preprocess matching files before serving them to the browser
     // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
     preprocessors: {
     },
@@ skipping 61 matching lines @@
     // configuration.logLevel = config.LOG_DEBUG;
     configuration.client.captureConsole = true;
   }
 
   if (process.env.DDC_BROWSERS) {
     configuration.browsers = process.env.DDC_BROWSERS.split(':');
   }
 
   config.set(configuration);
 };