Error with gulp-changed since update to 2

I've updated from "gulp-compass": "^2.0.3" to "gulp-compass": "^2.1.0" and now I get and error:

```
/Users/adrian/Desktop/app/node_modules/gulp-changed/index.js:31
if (sourceFile.stat.mtime > targetStat.mtime) {
^
TypeError: Cannot read property 'mtime' of null
at /Users/adrian/Desktop/app/node_modules/gulp-changed/index.js:31:23
at Object.oncomplete (fs.js:108:15)
```

My gulp task:

``` javascript
gulp.task('sass-desktop', function () {
return gulp.src('scss/*.scss')
.pipe(plumber({
errorHandler: function (error) {
console.log(error.message);
this.emit('end');
}}))
.pipe(compass({
config_file: 'config.rb',
css: 'css',
sass: 'scss',
image: 'images',
debug: false,
require: ['susy', 'modular-scale']
}))
.on('error', function(error) {
// Would like to catch the error here
console.log(error);
this.emit('end');
})
.pipe(autoprefixer({
browsers: ['last 8 versions'],
cascade: false
}))
.pipe(changed('css', {extension: '.css'}))
.pipe(gulp.dest('css'))
});
```

Any ideas?

Any alternative for gulp-changed?

Reproduce the failure in the sass-desktop task using the shown Gulp pipeline, then inspect node_modules/gulp-changed/index.js around the mtime comparison. Compare behavior before and after the gulp-compass 2.1.0 update, and document a confirmed compatible fix or alternative for gulp-changed.

Written by the indexing model from the issue text.