Merge branch 'issue_15434' into 'master'

Fixes XSS injection

REF: https://gitlab.com/gitlab-org/gitlab-ce/issues/15434

**Without the fix**

![xss1](/uploads/0a7b0b15fb87066965a7c73f1dbaa815/xss1.gif)


**With the fix**

![xss2](/uploads/473cfa0aa80656f24c58aebf1fd97fff/xss2.gif)


See merge request !1952

app/assets/javascripts/commits.js.coffee

 class @CommitsList
   @timer = null
 
-  @init: (ref, limit) ->
+  @init: (limit) ->
     $("body").on "click", ".day-commits-table li.commit", (event) ->
       if event.target.nodeName != "A"
         location.href = $(this).attr("url")

app/views/projects/commits/show.html.haml

@@ -39,4 +39,4 @@
 = spinner
 
 :javascript
-  CommitsList.init("#{@ref}", #{@limit});
+  CommitsList.init(#{@limit});