Make plugin loading async

Summary: This diff makes plugin loading async, which we'd need in a browser env (either because we'd use `import()` or we need to fetch the source and than eval it), and deals with all the fallout of that

Reviewed By: timur-valiev

Differential Revision: D32669995

fbshipit-source-id: 73babf38a6757c451b8200c3b320409f127b8b5b

desktop/flipper-ui-core/src/PluginContainer.tsx

@@ -242,6 +242,10 @@ class PluginContainer extends PureComponent<Props, State> {
   }
 
   renderPluginInfo() {
+    if (isTest()) {
+      // Plugin info uses Antd animations, generating a gazillion warnings
+      return 'Stubbed plugin info';
+    }
     return <PluginInfo />;
   }