FEATURE: detect theme errors and catch them (#7589)

* FEATURE: detect theme errors and catch them

* Bump COMPILER_VERSION

* Feedback

* Override eslint no console for one line

* Can't use our ajax method

* remove emoji from translation file

app/assets/javascripts/discourse/lib/utilities.js.es6

@@ -660,5 +660,39 @@ export function postRNWebviewMessage(prop, value) {
   }
 }
 
+function reportToLogster(name, error) {
+  const data = {
+    message: `${name} theme/component is throwing errors`,
+    stacktrace: error.stack
+  };
+
+  Ember.$.ajax(`${Discourse.BaseUri}/logs/report_js_error`, {
+    data,
+    type: "POST",
+    cache: false
+  });
+}
+// this function is used in lib/theme_javascript_compiler.rb
+export function rescueThemeError(name, error, api) {
+  /* eslint-disable-next-line no-console */
+  console.error(`"${name}" error:`, error);
+  reportToLogster(name, error);
+
+  const currentUser = api.getCurrentUser();
+  if (!currentUser || !currentUser.admin) {
+    return;
+  }
+
+  const path = `${Discourse.BaseUri}/admin/customize/themes`;
+  const message = I18n.t("themes.broken_theme_alert", {
+    theme: name,
+    path: `<a href="${path}">${path}</a>`
+  });
+  const alertDiv = document.createElement("div");
+  alertDiv.classList.add("broken-theme-alert");
+  alertDiv.innerHTML = `⚠️ ${message}`;
+  document.body.prepend(alertDiv);
+}
+
 // This prevents a mini racer crash
 export default {};