ui: Cleanup class/struct forward declarations

chrome/browser/component_updater/supervised_user_whitelist_installer.cc

Index: chrome/browser/component_updater/supervised_user_whitelist_installer.cc
diff --git a/chrome/browser/component_updater/supervised_user_whitelist_installer.cc b/chrome/browser/component_updater/supervised_user_whitelist_installer.cc
index ade964db53e3164a7f2a1ba7bd3fd634d4ec6a4c..d0e79cc75ef8cf49232563042cf1ae2ad670a5f1 100644
--- a/chrome/browser/component_updater/supervised_user_whitelist_installer.cc
+++ b/chrome/browser/component_updater/supervised_user_whitelist_installer.cc
@@ -40,6 +40,7 @@
 #include "components/prefs/pref_service.h"
 #include "components/prefs/scoped_user_pref_update.h"
 #include "components/safe_json/json_sanitizer.h"
+#include "components/update_client/update_client_errors.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace component_updater {
@@ -252,8 +253,9 @@ class SupervisedUserWhitelistComponentInstallerTraits
                           const base::FilePath& install_dir) const override;
   bool SupportsGroupPolicyEnabledComponentUpdates() const override;
   bool RequiresNetworkEncryption() const override;
-  bool OnCustomInstall(const base::DictionaryValue& manifest,
-                       const base::FilePath& install_dir) override;
+  update_client::CrxInstaller::Result OnCustomInstall(
+      const base::DictionaryValue& manifest,
+      const base::FilePath& install_dir) override;
   void ComponentReady(const base::Version& version,
                       const base::FilePath& install_dir,
                       std::unique_ptr<base::DictionaryValue> manifest) override;
@@ -288,11 +290,16 @@ bool SupervisedUserWhitelistComponentInstallerTraits::
   return true;
 }
 
-bool SupervisedUserWhitelistComponentInstallerTraits::OnCustomInstall(
+update_client::CrxInstaller::Result
+SupervisedUserWhitelistComponentInstallerTraits::OnCustomInstall(
     const base::DictionaryValue& manifest,
     const base::FilePath& install_dir) {
   // Delete the existing sanitized whitelist.
-  return base::DeleteFile(GetSanitizedWhitelistPath(crx_id_), false);
+  const bool success =
+      base::DeleteFile(GetSanitizedWhitelistPath(crx_id_), false);
+  return update_client::CrxInstaller::Result(
+      success ? update_client::InstallError::NONE
+              : update_client::InstallError::GENERIC_ERROR);
 }
 
 void SupervisedUserWhitelistComponentInstallerTraits::ComponentReady(