Add test:browser task for running the test suite against the merged browser script.

src/browser.coffee

@@ -34,6 +34,6 @@ processScripts = ->
         setTimeout -> CoffeeScript.run script.innerHTML
   null
 if window.addEventListener
-  addEventListener 'DOMContentLoaded', processScripts, false
+  window.addEventListener 'DOMContentLoaded', processScripts, false
 else
-  attachEvent 'onload', processScripts
+  window.attachEvent 'onload', processScripts

src/coffee-script.coffee

@@ -22,6 +22,9 @@ else if require.registerExtension
 # The current CoffeeScript version number.
 exports.VERSION = '0.9.4'
 
+# Expose helpers for testing.
+exports.helpers = require './helpers'
+
 # Compile a string of CoffeeScript code to JavaScript, using the Coffee/Jison
 # compiler.
 exports.compile = compile = (code, options) ->