fix: update GetPlugins to GetPluginsAsync for API change

The upstream Chromium API changed:
- Old: GetPlugins(callback) - took a callback
- New: GetPluginsAsync(callback) - async version takes a callback
- New: GetPlugins() - synchronous, no arguments

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

shell/browser/electron_plugin_info_host_impl.cc

@@ -36,7 +36,7 @@ void ElectronPluginInfoHostImpl::GetPluginInfo(const GURL& url,
                                                GetPluginInfoCallback callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   GetPluginInfo_Params params = {url, origin, mime_type};
-  PluginService::GetInstance()->GetPlugins(
+  PluginService::GetInstance()->GetPluginsAsync(
       base::BindOnce(&ElectronPluginInfoHostImpl::PluginsLoaded,
                      weak_factory_.GetWeakPtr(), params, std::move(callback)));
 }