Fix js error on merge request page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/javascripts/merge_request.js.coffee

@@ -10,7 +10,6 @@ class @MergeRequest
   #   action - String, current controller action
   #
   constructor: (@opts) ->
-    @initContextWidget()
     this.$el = $('.merge-request')
 
     this.$('.show-all-commits').on 'click', =>