Coverage on v0.12

I can't see my xml coverage anymore with Karma 0.12. Was working with old Kama versions.

This is my configuration:

``` javascript
module.exports = {
port: 9876,
captureTimeout: 60000,
frameworks: ['jasmine'],
basePath: 'app/build',
singleRun: true,
browsers: [
'Chrome',
'Firefox'
],
plugins: [
'karma-jasmine',
'karma-coverage',
'karma-story-reporter',
'karma-phantomjs-launcher',
'karma-firefox-launcher',
'karma-chrome-launcher'
],
files: [
'all my files'
],
exclude: [
'**/*.scenario.js'
],
reporters: ['coverage', 'dots'],
preprocessors: {
'!(bower_components)/**/!(*.spec).js': 'coverage'
},
coverageReporter: {
type : 'cobertura',
dir : '../coverage',
file: 'coverage.xml'
}
};
```