Remove RuntimeAPIDelegate::GetPreviousVersion.

extensions/browser/test_runtime_api_delegate.cc

 // Copyright 2014 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 "extensions/browser/test_runtime_api_delegate.h"
 
 #include "extensions/common/api/runtime.h"
 
 namespace extensions {
 
 using api::runtime::PlatformInfo;
 
 TestRuntimeAPIDelegate::TestRuntimeAPIDelegate() {
 }
 
 TestRuntimeAPIDelegate::~TestRuntimeAPIDelegate() {
 }
 
 void TestRuntimeAPIDelegate::AddUpdateObserver(UpdateObserver* observer) {
 }
 
 void TestRuntimeAPIDelegate::RemoveUpdateObserver(UpdateObserver* observer) {
 }
 
-base::Version TestRuntimeAPIDelegate::GetPreviousExtensionVersion(
-    const Extension* extension) {
-  return base::Version();
-}
-
 void TestRuntimeAPIDelegate::ReloadExtension(const std::string& extension_id) {
 }
 
 bool TestRuntimeAPIDelegate::CheckForUpdates(
     const std::string& extension_id,
     const UpdateCheckCallback& callback) {
   return false;
 }
 
 void TestRuntimeAPIDelegate::OpenURL(const GURL& uninstall_url) {
 }
 
 bool TestRuntimeAPIDelegate::GetPlatformInfo(PlatformInfo* info) {
   // TODO(rockot): This probably isn't right. Maybe this delegate should just
   // support manual PlatformInfo override for tests if necessary.
   info->os = api::runtime::PLATFORM_OS_CROS;
   return true;
 }
 
 bool TestRuntimeAPIDelegate::RestartDevice(std::string* error_message) {
   return false;
 }
 
 }  // namespace extensions