title: Eslint flags as not defined class member that acts as default argument value
body: <p>Why after upgrading from:</p>
  <pre><code>    &quot;@typescript-eslint/eslint-plugin&quot;: &quot;^4.13.0&quot;,
      &quot;@typescript-eslint/parser&quot;: &quot;^4.13.0&quot;,
  </code></pre>
  <p>to:</p>
  <pre><code>    &quot;@typescript-eslint/eslint-plugin&quot;: &quot;^4.14.0&quot;,
      &quot;@typescript-eslint/parser&quot;: &quot;^4.14.0&quot;,
  </code></pre>
  <p>eslint has started to flag in the class below (written in Typescript) <code>currentPalette</code> as not defined [eslint(no-undef)] where it acts as default argument for <code>whichPalette</code>?</p>
  <pre><code>class Colormap {
  
      private currentPalette: string;
  
      getColors(numberColors: number, whichPalette = this.currentPalette): string[] {
          const colors = palette(whichPalette, numberColors);
          return colors.map((color) =&gt; `#${color}`);
      }
  }
  </code></pre>
  <p>Thanks for clarifying!</p>