Put grey block around blob ref switcher and breadcrumb.

app/views/projects/blob/_blob.html.haml

-%ul.breadcrumb.repo-breadcrumb
+.gray-content-block.top-block
+  .tree-ref-holder
+    = render 'shared/ref_switcher', destination: 'blob', path: @path
+
+  %ul.breadcrumb.repo-breadcrumb
     %li
-    %i.fa.fa-angle-right
       = link_to namespace_project_tree_path(@project.namespace, @project, @ref) do
         = @project.path
     - tree_breadcrumbs(@tree, 6) do |title, path|

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

@@ -3,9 +3,6 @@
 
 = render 'projects/last_push'
 
-%div.tree-ref-holder
-  = render 'shared/ref_switcher', destination: 'blob', path: @path
-
 %div#tree-holder.tree-holder
   = render 'blob', blob: @blob