Allow for dynamically updated fontSizes in CodePane (#875)

* Look for props first, then use theme

* Changelog++

Author: Kylie Stewart

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Allow for `props.fontSize` to override the theme's monospace font size in `CodePane`. [#875](https://github.com/FormidableLabs/spectacle/pull/875)
 - Surface `textDecoration` prop from styled-system for `Link`s. [#869](https://github.com/FormidableLabs/spectacle/pull/869)
 
 ## 6.0.1

src/components/code-pane.js

@@ -39,14 +39,20 @@ export default function CodePane(props) {
   }, [themeContext]);
 
   const fontSize = React.useMemo(() => {
+    if (props && props.fontSize) {
+      return props.fontSize;
+    }
+
     if (
       themeContext &&
       themeContext.fontSizes &&
       themeContext.fontSizes.monospace
     ) {
       return themeContext.fontSizes.monospace;
     }
-    return props.fontSize;
+
+    // Default to 15px
+    return 15;
   }, [themeContext, props.fontSize]);
 
   const preStyles = React.useMemo(
@@ -159,7 +165,6 @@ CodePane.propTypes = {
 CodePane.defaultProps = {
   language: 'javascript',
   theme: theme,
-  fontSize: 15,
   highlightStart: -Infinity,
   highlightEnd: Infinity
 };