Revert of Makes the component installers return a Result instead of a bool.

chrome/browser/component_updater/sth_set_component_installer.h

Index: chrome/browser/component_updater/sth_set_component_installer.h
diff --git a/chrome/browser/component_updater/sth_set_component_installer.h b/chrome/browser/component_updater/sth_set_component_installer.h
index 0afadb48bb7fc8655c9611e4a6c87d8921fdbb14..1523d7a011814ce8f00b6c85fbe824c8b9022c1c 100644
--- a/chrome/browser/component_updater/sth_set_component_installer.h
+++ b/chrome/browser/component_updater/sth_set_component_installer.h
@@ -50,9 +50,8 @@
   // ComponentInstallerTraits implementation.
   bool SupportsGroupPolicyEnabledComponentUpdates() const override;
   bool RequiresNetworkEncryption() const override;
-  update_client::CrxInstaller::Result OnCustomInstall(
-      const base::DictionaryValue& manifest,
-      const base::FilePath& install_dir) override;
+  bool OnCustomInstall(const base::DictionaryValue& manifest,
+                       const base::FilePath& install_dir) override;
   bool VerifyInstallation(const base::DictionaryValue& manifest,
                           const base::FilePath& install_dir) const override;
   void ComponentReady(const base::Version& version,