seo: remove obsolete itemprop microdata attributes.

Remove obsolete itemprop attributes. These were originally added in
2dd4b4c, but they haven't been working since e334c34 removed the
itemscope and itemtype attributes. They never worked right because they
weren't nested properly, and they were never really useful because
Google doesn't use the ImageObject schema for anything.

* https://developers.google.com/search/docs/guides/intro-structured-data
* https://developer.mozilla.org/en-US/docs/Web/HTML/Microdata
* https://schema.org/docs/gs.html
* https://schema.org/ImageObject

app/presenters/tag_set_presenter.rb

@@ -125,8 +125,7 @@ class TagSetPresenter
     end
 
     humanized_tag = humanize_tags ? name.tr("_", " ") : name
-    itemprop = 'itemprop="author"' if tag.artist?
-    html << %{<a class="search-tag" #{itemprop} href="/posts?tags=#{u(name)}">#{h(humanized_tag)}</a> }
+    html << %{<a class="search-tag" href="/posts?tags=#{u(name)}">#{h(humanized_tag)}</a> }
 
     unless name_only || tag.new_record?
       if count >= 10_000

app/views/posts/partials/show/_image.html.erb

@@ -1,3 +1,3 @@
 <% if policy(post).visible? %>
-  <%= image_tag(post.file_url_for(CurrentUser.user), width: post.image_width_for(CurrentUser.user), height: post.image_height_for(CurrentUser.user), id: "image", class: "fit-width", "data-original-width": post.image_width, "data-original-height": post.image_height, "data-large-width": post.large_image_width, "data-large-height": post.large_image_height, "data-tags": post.tag_string, alt: post.presenter.humanized_essential_tag_string, "data-uploader": post.uploader.name, "data-rating": post.rating, "data-flags": post.status_flags, "data-parent-id": post.parent_id, "data-has-children": post.has_children?, "data-has-active-children": post.has_active_children?, "data-score": post.score, "data-fav-count": post.fav_count, "itemprop": "contentUrl") %>
+  <%= image_tag(post.file_url_for(CurrentUser.user), width: post.image_width_for(CurrentUser.user), height: post.image_height_for(CurrentUser.user), id: "image", class: "fit-width", "data-original-width": post.image_width, "data-original-height": post.image_height, "data-large-width": post.large_image_width, "data-large-height": post.large_image_height, "data-tags": post.tag_string, alt: post.presenter.humanized_essential_tag_string, "data-uploader": post.uploader.name, "data-rating": post.rating, "data-flags": post.status_flags, "data-parent-id": post.parent_id, "data-has-children": post.has_children?, "data-has-active-children": post.has_active_children?, "data-score": post.score, "data-fav-count": post.fav_count) %>
 <% end %>

app/views/posts/partials/show/_information.html.erb

@@ -8,7 +8,6 @@
   <% end %>
   <li id="post-info-date">
     Date: <%= link_to time_ago_in_words_tagged(post.created_at), posts_path(tags: "date:#{post.created_at.to_date}") %>
-    <meta itemprop="uploadDate" content="<%= post.created_at.iso8601 %>">
   </li>
   <% if post.approver %>
     <li id="post-info-approver">
@@ -19,7 +18,7 @@
   <li id="post-info-size">
     Size: <%= link_to_if policy(post).visible?, number_to_human_size(post.file_size), post.tagged_file_url %>
     <% if post.has_dimensions? %>
-      (<span itemprop="width"><%= post.image_width %></span>x<span itemprop="height"><%= post.image_height %></span>)
+      (<%= post.image_width %>x<%= post.image_height %>)
     <% end %>
   </li>
   <li id="post-info-source">Source: <%= post_source_tag(post.source, post.normalized_source) %></li>

app/views/uploads/show.html.erb

@@ -13,7 +13,7 @@
         <li>
           Size: <%= number_to_human_size(@upload.file_size) %></li>
           <% if @upload.image_width.present? %>
-            (<span itemprop="width"><%= @upload.image_width %></span>x<span itemprop="height"><%= @upload.image_height %></span>)
+            (<%= @upload.image_width %>x<%= @upload.image_height %>)
           <% end %>
         </li>
       <% end %>