Endorsement username shouldn't be broken

If we endourse the answer of the question in discussion
the username link that is created is broken whereas it
should point to the userprofile.

TNL-188

common/static/coffee/spec/discussion/view/thread_response_show_view_spec.coffee

@@ -45,6 +45,7 @@ describe "ThreadResponseShowView", ->
     it "renders endorsement correctly for a marked answer in a question thread", ->
         endorsement = {
           "username": "test_endorser",
+          "user_id": "test_id",
           "time": new Date().toISOString()
         }
         @thread.set("thread_type", "question")
@@ -56,6 +57,7 @@ describe "ThreadResponseShowView", ->
         expect(@view.$(".posted-details").text().replace(/\s+/g, " ")).toMatch(
           "marked as answer less than a minute ago by " + endorsement.username
         )
+        expect(@view.$(".posted-details > a").attr('href')).toEqual("/courses/edX/999/test/discussion/forum/users/test_id")
 
     it "renders anonymous endorsement correctly for a marked answer in a question thread", ->
         endorsement = {
@@ -74,6 +76,7 @@ describe "ThreadResponseShowView", ->
     it "renders endorsement correctly for an endorsed response in a discussion thread", ->
         endorsement = {
           "username": "test_endorser",
+          "user_id": "test_id",
           "time": new Date().toISOString()
         }
         @thread.set("thread_type", "discussion")
@@ -85,6 +88,7 @@ describe "ThreadResponseShowView", ->
         expect(@view.$(".posted-details").text().replace(/\s+/g, " ")).toMatch(
           "endorsed less than a minute ago by " + endorsement.username
         )
+        expect(@view.$(".posted-details > a").attr('href')).toEqual("/courses/edX/999/test/discussion/forum/users/test_id")
 
     it "renders anonymous endorsement correctly for an endorsed response in a discussion thread", ->
         endorsement = {

common/static/coffee/src/discussion/views/discussion_content_view.coffee

@@ -194,7 +194,7 @@ if Backbone?
       url = @model.urlFor("endorse")
       updates =
         endorsed: is_endorsing
-        endorsement: if is_endorsing then {username: DiscussionUtil.getUser().get("username"), time: new Date().toISOString()} else null
+        endorsement: if is_endorsing then {username: DiscussionUtil.getUser().get("username"), user_id: DiscussionUtil.getUser().id, time: new Date().toISOString()} else null
       if @model.get('thread').get('thread_type') == 'question'
         if is_endorsing
           msg = gettext("We had some trouble marking this response as an answer.  Please try again.")