Refactor discussion reply

app/views/notes/_discussion_reply_button.html.haml

+= link_to "javascript:;",
+          class: "btn reply-btn js-discussion-reply-button",
+          data: { noteable_type: note.noteable_type,
+                  noteable_id:   note.noteable_id,
+                  line_code:     note.line_code,
+                  discussion_id: note.discussion_id },
+          title: "Add a reply" do
+  %i.icon-comment
+  Reply

app/views/notes/_notes_with_form.html.haml

 %ul#notes-list.notes
-%ul#new-notes-list.notes
-.notes-status
 - if can? current_user, :write_note, @project
   .note-forms.js-note-forms
     = render "notes/common_form"
-    = render "notes/diff_note_form"
+    = render "notes/discussion_note_form"
 :javascript
   $(function(){
-    NoteList.init("#{tid}", "#{tt}", "#{project_notes_path(@project)}");
+    NoteList.init("#{@target_id}", "#{@target_type}", "#{project_notes_path(@project)}");
   });

app/views/notes/_reversed_notes_with_form.html.haml

@@ -7,5 +7,5 @@
 :javascript
   $(function(){
-    NoteList.init("#{tid}", "#{tt}", "#{project_notes_path(@project)}");
+    NoteList.init("#{@target_id}", "#{@target_type}", "#{project_notes_path(@project)}");
   });

app/views/notes/create.js.haml

-- if @note.line_code
-  = render "create_diff_note", note: @note
-- else
+- if note_for_main_target?(@note)
   = render "create_common_note", note: @note
+- else
+  = render "create_discussion_note", note: @note

app/views/projects/wall.html.haml

 %div.wall_page
-  = render "notes/reversed_notes_with_form", tid: nil, tt: "wall"
+  = render "notes/reversed_notes_with_form"

app/views/snippets/show.html.haml

@@ -8,4 +8,4 @@
 %br
 %div= render 'blob'
-%div#notes= render "notes/notes_with_form", tid: @snippet.id, tt: "snippet"
+%div#notes= render "notes/notes_with_form"