Revert "PERF: Move highlightjs to a background worker, and add result cache (#10191)"

This caused a CORS error when used with S3 asset storage

This reverts commit d09f283e91.

app/assets/javascripts/admin/components/highlighted-code.js

@@ -1,37 +1,11 @@
 import Component from "@ember/component";
-import { highlightText } from "discourse/lib/highlight-syntax";
-import { escapeExpression } from "discourse/lib/utilities";
-import discourseComputed from "discourse-common/utils/decorators";
-import { htmlSafe } from "@ember/template";
+import { on, observes } from "discourse-common/utils/decorators";
+import highlightSyntax from "discourse/lib/highlight-syntax";
 
 export default Component.extend({
-  didReceiveAttrs() {
-    this._super(...arguments);
-    if (this.code === this.previousCode) return;
-
-    this.set("previousCode", this.code);
-    this.set("highlightResult", null);
-    const toHighlight = this.code;
-    highlightText(escapeExpression(toHighlight), this.lang).then(
-      ({ result }) => {
-        if (toHighlight !== this.code) return; // Code has changed since highlight was requested
-        this.set("highlightResult", result);
-      }
-    );
-  },
-
-  @discourseComputed("code", "highlightResult")
-  displayCode(code, highlightResult) {
-    if (highlightResult) return htmlSafe(highlightResult);
-    return code;
-  },
-
-  @discourseComputed("highlightResult", "lang")
-  codeClasses(highlightResult, lang) {
-    const classes = [];
-    if (lang) classes.push(lang);
-    if (highlightResult) classes.push("hljs");
-
-    return classes.join(" ");
+  @on("didInsertElement")
+  @observes("code")
+  _refresh: function() {
+    highlightSyntax($(this.element));
   }
 });

app/assets/javascripts/admin/models/theme.js

@@ -7,8 +7,8 @@ import discourseComputed from "discourse-common/utils/decorators";
 import { popupAjaxError } from "discourse/lib/ajax-error";
 import { ajax } from "discourse/lib/ajax";
 import { escapeExpression } from "discourse/lib/utilities";
-import { url } from "discourse/lib/computed";
 import highlightSyntax from "discourse/lib/highlight-syntax";
+import { url } from "discourse/lib/computed";
 
 const THEME_UPLOAD_VAR = 2;
 const FIELDS_IDS = [0, 1, 5];
@@ -321,7 +321,7 @@ const Theme = RestModel.extend({
             }
           }
         );
-        highlightSyntax(document.querySelector(".bootbox.modal"));
+        highlightSyntax();
       } else {
         return this.save({ remote_update: true }).then(() =>
           this.set("changed", false)

app/assets/javascripts/admin/templates/components/highlighted-code.hbs

@@ -1 +1 @@
-<pre><code class={{codeClasses}}>{{displayCode}}</code></pre>
+<pre><code class={{lang}}>{{code}}</code></pre>