`blocks_on.html.erb` is almost identical to `block_by.html.erb`. Add a newline to align with the other file (makes it easier to see the more subtle important difference)
<% content_for :heading do %>
<h1><%= t(".heading_html", :name => link_to(@user.display_name, user_path(@user))) %></h1>
<% end %>
+
<% unless @user_blocks.empty? %>
<%= render :partial => "blocks", :locals => { :show_revoke_link => can?(:revoke, UserBlock), :show_user_name => false, :show_creator_name => true } %>
<% else %>