Use PreloadCheckGroup in ExtensionInstallChecker. Make RequirementsChecker a PreloadCheck.

extensions/browser/api/management/management_api.h

Index: extensions/browser/api/management/management_api.h
diff --git a/extensions/browser/api/management/management_api.h b/extensions/browser/api/management/management_api.h
index 785af73f6d71fc16d27bb04a749f96cfca0b0f76..6f022c81f97be7a1a37fad8349a54eb83fe189b8 100644
--- a/extensions/browser/api/management/management_api.h
+++ b/extensions/browser/api/management/management_api.h
@@ -11,6 +11,7 @@
 #include "base/strings/string16.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "extensions/browser/api/management/management_api_delegate.h"
+#include "extensions/browser/preload_check.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_event_histogram_value.h"
@@ -112,7 +113,7 @@ class ManagementSetEnabledFunction : public UIThreadExtensionFunction {
  private:
   void OnInstallPromptDone(bool did_accept);
 
-  void OnRequirementsChecked(const std::vector<std::string>& requirements);
+  void OnRequirementsChecked(PreloadCheck::Errors requirements_errors);
 
   std::string extension_id_;