title: add_image_size for custom logo in Wordpress
body: <p>I am using the following code to enable users to upload a custom logo for my wordpress theme:</p>
  
  <pre><code>function mytheme_setup() {
      add_theme_support('custom-logo');
  }
  
  add_action('after_setup_theme', 'mytheme_setup');
  </code></pre>
  
  <p>I have tried implementing <code>add_image_size</code> to render the logo at 180x180px with this:</p>
  
  <pre><code>add_image_size('mytheme-logo', 180, 180);
  add_theme_support('custom-logo', array(
      'size' =&gt; 'mytheme-logo'
  ));
  </code></pre>
  
  <p>To display the logo in my theme, I have used:</p>
  
  <pre><code>&lt;?php
      // Display the Custom Logo
      the_custom_logo('mytheme-logo');
      // No Custom Logo, just display the site's name
      if (!has_custom_logo()) {
  ?&gt;
          &lt;h1 style="text-align:center;"&gt;&lt;?php bloginfo('name'); ?&gt;&lt;/h1&gt;
          &lt;?php
      }
  ?&gt;
  </code></pre>
  
  <p>So I am able to upload and display the logo now, but it seems that the image is not affected by the <code>add_image_size</code>. The image is not resized by wordrpress and this is a problem because it may affect loading time of the website.</p>
  
  <p>Am I doing something wrong here?</p>