title: Multiline mat-tooltip on mat-table cell is not working
body: <p>I made mat-tooltip as multiline with following style in global css.</p>
  <pre><code> .mat-tooltip-class-here {
    white-space: pre-line !important;
   }
  </code></pre>
  <p>This is working on span and button but not on mat cell.</p>
  <p><strong>see on span</strong> (Working):</p>
  <p><a href="https://i.stack.imgur.com/474Gn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/474Gn.png" alt="tooltip on span" /></a></p>
  <p><strong>see on button</strong> (Working):</p>
  <p><a href="https://i.stack.imgur.com/iqDyV.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/iqDyV.png" alt="enter image description here" /></a></p>
  <p><strong>see on table cell</strong> (Not working):</p>
  <p><a href="https://i.stack.imgur.com/yisE4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yisE4.png" alt="enter image description here" /></a></p>
  <p>Not sure what is issue. I have created stackblitz here: <a href="https://stackblitz.com/edit/angular-4mtwsw" rel="nofollow noreferrer">https://stackblitz.com/edit/angular-4mtwsw</a></p>