title: gulpif doesn't work with del
body: <p>with this code:</p>
  
  <pre><code> global.release = argv.release;
      var gulp = require('gulp');
      var gulpif = require('gulp-if');
      var del = require('del');
  
      module.exports = gulp.task('clean', function (cb) {
          return gulpif(release, del([TMP_FOLDER, PHONEGAP_FOLDER],cb), del([TMP_FOLDER, BUILD_FOLDER],cb));
      });
  </code></pre>
  
  <p>I've got this error:</p>
  
  <pre><code>[14:07:35] Starting 'default'...
  [14:07:35] Starting 'clean'...
  undefined
  [14:07:35] 'clean' errored after 6.11 ms
  [14:07:35] Error: gulp-if: child action is required
      at module.exports (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp-if/index.js:10:9)
      at Gulp.&lt;anonymous&gt; (/home/user/github/angular-bootstrap-cordova-seed/gulp/tasks/clean.js:8:12)
      at module.exports (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:34:7)
      at Gulp.Orchestrator._runTask (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/index.js:273:3)
      at Gulp.Orchestrator._runStep (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/index.js:214:10)
      at Gulp.Orchestrator.start (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/index.js:134:8)
      at runNextSet (/home/user/github/angular-bootstrap-cordova-seed/node_modules/run-sequence/index.js:74:16)
      at runSequence (/home/user/github/angular-bootstrap-cordova-seed/node_modules/run-sequence/index.js:85:2)
      at Gulp.&lt;anonymous&gt; (/home/user/github/angular-bootstrap-cordova-seed/gulp/tasks/default.js:15:9)
      at module.exports (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:34:7)
  Error running task sequence: { task: 'clean',
    message: 'clean catch',
    duration: 0.006112762,
    hrDuration: [ 0, 6112762 ],
    err: [Error: gulp-if: child action is required] }
  [14:07:35] Finished 'default' after 13 ms
  [14:07:35] 'clean' errored after 15 ms
  [14:07:35] Error: task completion callback called too many times
      at finish (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:15:10)
      at cb (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:29:3)
      at module.exports (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/each-async/index.js:22:3)
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/index.js:34:3
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:277:13
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:157:25
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:274:17
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/index.js:38:4
      at f (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/glob/node_modules/once/once.js:17:25)
      at Glob.&lt;anonymous&gt; (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/glob/glob.js:129:7)
  [14:07:35] 'clean' errored after 16 ms
  [14:07:35] Error: task completion callback called too many times
      at finish (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:15:10)
      at cb (/home/user/github/angular-bootstrap-cordova-seed/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:29:3)
      at module.exports (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/each-async/index.js:22:3)
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/index.js:34:3
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:277:13
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:157:25
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/async/lib/async.js:274:17
      at /home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/index.js:38:4
      at f (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/glob/node_modules/once/once.js:17:25)
      at Glob.&lt;anonymous&gt; (/home/user/github/angular-bootstrap-cordova-seed/node_modules/del/node_modules/globby/node_modules/glob/glob.js:129:7)
  </code></pre>
  
  <p>is it a bug ?
  if not what's the matter ?</p>