title: Mat-icon does not center in its div
body: <p>I am very new to css and I cannot align the mat-icon (the thought bubble) to the div class=img (the green square on the left) - see the attached image. At this moment the icon is a little bit near the top</p>
  
  <p>For adding the svg icon I used Material Angular - MatIconRegistry class (don't know if it matters)</p>
  
  <p>My result:
  <a href="https://i.stack.imgur.com/mdJKn.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/mdJKn.jpg" alt="enter image description here"></a></p>
  
  <p>Here is my html:</p>
  
  <pre><code>&lt;div class="container"&gt;
    &lt;div class="img"&gt;&lt;mat-icon svgIcon="info"&gt;&lt;/mat-icon&gt;&lt;/div&gt;
    Some text here!
  &lt;/div&gt;
  </code></pre>
  
  <p>Here is my css:</p>
  
  <pre><code>$conainer-min-width: 256px !default;
  $conainer-max-width: 512px !default;
  $conainer-height: 50px !default;
  
  div.container {
    max-width: $container-max-width;
    min-width: $container-min-width;
    height: $container-height;
    margin: auto;
    color: #000000;
    background-color: #ffffff;
    line-height: $container-height;
    text-align: center;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
    border-width: 1px;
    border-style: solid;
    border-color: #9e9e9e;
    padding-right: 20px;
    position: fixed;
    z-index: 1000;
    left: 0;
    right: 0;
    top: 30px;
  }
  
  
  div.img {
    width: $container-height;
    height: $container-height;
    float: left;
    display: block;
    margin: 0 auto;
    border-right-width: 1px;
    border-right-style: solid;
    border-right-color: #9e9e9e;
    line-height: $container-height;
    justify-content: center;
    background-color: #3f9c35;
  }
  </code></pre>
  
  <p>Any thoughts on how to fix this?</p>