Add support for uninstalling components and use it in SupervisedUserWhitelistInstaller.

chrome/browser/component_updater/recovery_component_installer.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/component_updater/recovery_component_installer.h"
 
 #include <stdint.h>
 #include <string>
 
 #include "base/base_paths.h"
@@ skipping 168 matching lines @@
 
   // ComponentInstaller implementation:
   void OnUpdateError(int error) override;
 
   bool 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;
+
  private:
   ~RecoveryComponentInstaller() override {}
 
   bool RunInstallCommand(const base::CommandLine& cmdline,
                          const base::FilePath& installer_folder) const;
 
   Version current_version_;
   PrefService* prefs_;
 };
 
@@ skipping 154 matching lines @@
   }
   return true;
 }
 
 bool RecoveryComponentInstaller::GetInstalledFile(
     const std::string& file,
     base::FilePath* installed_file) {
   return false;
 }
 
+bool RecoveryComponentInstaller::Uninstall() {
+  return false;
+}
+
 void RegisterRecoveryComponent(ComponentUpdateService* cus,
                                PrefService* prefs) {
 #if !defined(OS_CHROMEOS)
   if (SimulatingElevatedRecovery()) {
     BrowserThread::PostTask(
         BrowserThread::UI,
         FROM_HERE,
         base::Bind(&SimulateElevatedRecoveryHelper, prefs));
   }
 
@@ skipping 23 matching lines @@
 #endif  // OS_WIN
   prefs->SetBoolean(prefs::kRecoveryComponentNeedsElevation, false);
 }
 
 void DeclinedElevatedRecoveryInstall(PrefService* prefs) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   prefs->SetBoolean(prefs::kRecoveryComponentNeedsElevation, false);
 }
 
 }  // namespace component_updater