Include firefox in check to quote font families (#12288)

lib/web_ui/lib/src/engine/text/font_collection.dart

@@ -114,11 +114,11 @@ class _FontManager {
     String asset,
     Map<String, String> descriptors,
   ) {
-    // Safari crashes if you create a [html.FontFace] with a font family that
-    // is not correct CSS syntax. To ensure the font family is accepted on
-    // Safari, wrap it in quotes.
+    // Safari and Firefox crash if you create a [html.FontFace] with a font
+    // family that is not correct CSS syntax. To ensure the font family is
+    // accepted on these browsers, wrap it in quotes.
     // See: https://drafts.csswg.org/css-fonts-3/#font-family-prop
-    if (browserEngine == BrowserEngine.webkit) {
+    if (browserEngine == BrowserEngine.webkit || browserEngine == BrowserEngine.firefox) {
       family = "'$family'";
     }
     // try/catch because `new FontFace` can crash with an improper font family.