Use `icon` helper method in helper modules

app/helpers/commits_helper.rb

@@ -65,8 +65,7 @@ module CommitsHelper
     branches.sort.map do |branch|
       link_to(project_tree_path(project, branch)) do
         content_tag :span, class: 'label label-gray' do
-          content_tag(:i, nil, class: 'fa fa-code-fork') + ' ' +
-            branch
+          icon('code-fork') + ' ' + branch
         end
       end
     end.join(" ").html_safe
@@ -78,8 +77,7 @@ module CommitsHelper
     sorted.map do |tag|
       link_to(project_commits_path(project, project.repository.find_tag(tag).name)) do
         content_tag :span, class: 'label label-gray' do
-          content_tag(:i, nil, class: 'fa fa-tag') + ' ' +
-            tag
+          icon('tag') + ' ' + tag
         end
       end
     end.join(" ").html_safe

app/helpers/events_helper.rb

@@ -27,18 +27,17 @@ module EventsHelper
 
     content_tag :li, class: "filter_icon #{active}" do
       link_to request.path, class: 'has_tooltip event_filter_link', id: "#{key}_event_filter", 'data-original-title' => tooltip do
-        content_tag(:i, nil, class: icon_for_event[key]) +
-          content_tag(:span, ' ' + tooltip)
+        icon(icon_for_event[key]) + content_tag(:span, ' ' + tooltip)
       end
     end
   end
 
   def icon_for_event
     {
-      EventFilter.push     => 'fa fa-upload',
-      EventFilter.merged   => 'fa fa-check-square-o',
-      EventFilter.comments => 'fa fa-comments',
-      EventFilter.team     => 'fa fa-user',
+      EventFilter.push     => 'upload',
+      EventFilter.merged   => 'check-square-o',
+      EventFilter.comments => 'comments',
+      EventFilter.team     => 'user',
     }
   end
 

app/helpers/issues_helper.rb

@@ -62,7 +62,7 @@ module IssuesHelper
       ts << capture_haml do
         haml_tag :span do
           haml_concat '&middot;'
-          haml_concat '<i class="fa fa-edit" title="edited"></i> '
+          haml_concat icon('edit', title: 'edited')
           haml_concat time_ago_with_tooltip(issue.updated_at, 'bottom', 'issue_edited_ago')
         end
       end

app/helpers/notes_helper.rb

@@ -22,7 +22,7 @@ module NotesHelper
       ts << capture_haml do
         haml_tag :span do
           haml_concat '&middot;'
-          haml_concat '<i class="fa fa-edit" title="edited"></i> '
+          haml_concat icon('edit', title: 'edited')
           haml_concat time_ago_with_tooltip(note.updated_at, 'bottom', 'note_edited_ago')
         end
       end
@@ -57,7 +57,7 @@ module NotesHelper
     button_tag(class: 'btn add-diff-note js-add-diff-note-button',
                data: data,
                title: 'Add a comment to this line') do
-      content_tag :i, nil, class: 'fa fa-comment-o'
+      icon('comment-o')
     end
   end
 
@@ -74,7 +74,7 @@ module NotesHelper
 
     button_tag class: 'btn reply-btn js-discussion-reply-button',
                data: data, title: 'Add a reply' do
-      link_text = content_tag(:i, nil, class: 'fa fa-comment')
+      link_text = icon('comment')
       link_text << ' Reply'
     end
   end

app/helpers/notifications_helper.rb

 module NotificationsHelper
   def notification_icon(notification)
     if notification.disabled?
-      content_tag :i, nil, class: 'fa fa-volume-off ns-mute'
+      icon('volume-off', class: 'ns-mute')
     elsif notification.participating?
-      content_tag :i, nil, class: 'fa fa-volume-down ns-part'
+      icon('volume-down', class: 'ns-part')
     elsif notification.watch?
-      content_tag :i, nil, class: 'fa fa-volume-up ns-watch'
+      icon('volume-up', class: 'ns-watch')
     else
-      content_tag :i, nil, class: 'fa fa-circle-o ns-default'
+      icon('circle-o', class: 'ns-default')
     end
   end
 end

app/helpers/projects_helper.rb

@@ -83,7 +83,7 @@ module ProjectsHelper
                       ' Star'
                     end
 
-      content_tag('i', ' ', class: 'fa fa-star') + toggle_text
+      icon('star') + toggle_text
     end
 
     count_html = content_tag('span', class: 'count') do
@@ -107,7 +107,7 @@ module ProjectsHelper
   end
 
   def link_to_toggle_fork
-    out = content_tag(:i, '', class: 'fa fa-code-fork')
+    out = icon('code-fork')
     out << ' Fork'
     out << content_tag(:span, class: 'count') do
       @project.forks_count.to_s

app/helpers/tree_helper.rb

@@ -38,13 +38,8 @@ module TreeHelper
   #
   # type - String type of the tree item; either 'folder' or 'file'
   def tree_icon(type)
-    icon_class = if type == 'folder'
-                   'fa fa-folder'
-                 else
-                   'fa fa-file-o'
-                 end
-
-    content_tag :i, nil, class: icon_class
+    icon_class = type == 'folder' ? 'folder' : 'file-o'
+    icon(icon_class)
   end
 
   def tree_hex_class(content)