Simplify image support detection for SW

Instead of using extra files + a plugin to inline images, report image support from the main thread before caching assets.

rollup.config.js

@@ -30,7 +30,6 @@ import emitFiles from './lib/emit-files-plugin';
 import featurePlugin from './lib/feature-plugin';
 import initialCssPlugin from './lib/initial-css-plugin';
 import serviceWorkerPlugin from './lib/sw-plugin';
-import dataURLPlugin from './lib/data-url-plugin';
 import entryDataPlugin from './lib/entry-data-plugin';
 
 function resolveFileUrl({ fileName }) {
@@ -82,7 +81,6 @@ export default async function ({ watch }) {
       'codecs',
     ]),
     urlPlugin(),
-    dataURLPlugin(),
     cssPlugin(resolveFileUrl),
   ];