ui: Cleanup class/struct forward declarations

ios/chrome/browser/net/crl_set_fetcher.h

Index: ios/chrome/browser/net/crl_set_fetcher.h
diff --git a/ios/chrome/browser/net/crl_set_fetcher.h b/ios/chrome/browser/net/crl_set_fetcher.h
index 5f0574246732d7b9964615933a76f3b5b18241cb..88821a9eb565ed888fb3612fa79783b6403cc78f 100644
--- a/ios/chrome/browser/net/crl_set_fetcher.h
+++ b/ios/chrome/browser/net/crl_set_fetcher.h
@@ -40,8 +40,8 @@ class CRLSetFetcher : public update_client::CrxInstaller {
 
   // ComponentInstaller interface
   void OnUpdateError(int error) override;
-  bool Install(const base::DictionaryValue& manifest,
-               const base::FilePath& unpack_path) override;
+  Result Install(const base::DictionaryValue& manifest,
+                 const base::FilePath& unpack_path) override;
   bool GetInstalledFile(const std::string& file,
                         base::FilePath* installed_file) override;
   bool Uninstall() override;
@@ -79,6 +79,9 @@ class CRLSetFetcher : public update_client::CrxInstaller {
   // the disk.
   void DoDeleteFromDisk();
 
+  bool DoInstall(const base::DictionaryValue& manifest,
+                 const base::FilePath& unpack_path);
+
   component_updater::ComponentUpdateService* cus_;
 
   // Path where the CRL file is stored.