Move ExtensionCache to //extensions

chrome/browser/extensions/updater/extension_cache.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 "chrome/browser/extensions/updater/extension_cache.h"
-
-#include "base/memory/singleton.h"
-
-#if defined(OS_CHROMEOS)
-#include "chrome/browser/extensions/updater/extension_cache_impl.h"
-#endif  // OS_CHROMEOS
-
-namespace extensions {
-namespace {
-
-#if !defined(OS_CHROMEOS)
-
-// Implementation of ExtensionCache that doesn't cache anything.
-// Real cache is used only on Chrome OS other OSes use this null implementation.
-class ExtensionCacheNullImpl : public ExtensionCache {
- public:
-  static ExtensionCacheNullImpl* GetInstance() {
-    return Singleton<ExtensionCacheNullImpl>::get();
-  }
-
-  // Implementation of ExtensionCache.
-  virtual void Start(const base::Closure& callback) override {
-    callback.Run();
-  }
-
-  virtual void Shutdown(const base::Closure& callback) override {
-    callback.Run();
-  }
-
-  virtual void AllowCaching(const std::string& id) override {
-  }
-
-  virtual bool GetExtension(const std::string& id,
-                            base::FilePath* file_path,
-                            std::string* version) override {
-    return false;
-  }
-
-  virtual void PutExtension(const std::string& id,
-                            const base::FilePath& file_path,
-                            const std::string& version,
-                            const PutExtensionCallback& callback) override {
-    callback.Run(file_path, true);
-  }
-
- private:
-  friend struct DefaultSingletonTraits<ExtensionCacheNullImpl>;
-
-  ExtensionCacheNullImpl() {}
-  virtual ~ExtensionCacheNullImpl() {}
-};
-
-#endif  // !OS_CHROMEOS
-
-static ExtensionCache* g_extension_cache_override = NULL;
-
-}  // namespace
-
-// static
-ExtensionCache* ExtensionCache::GetInstance() {
-  if (g_extension_cache_override) {
-    return g_extension_cache_override;
-  } else {
-#if defined(OS_CHROMEOS)
-    return ExtensionCacheImpl::GetInstance();
-#else
-    return ExtensionCacheNullImpl::GetInstance();
-#endif
-  }
-}
-
-// static
-ExtensionCache* ExtensionCache::SetForTesting(ExtensionCache* cache) {
-  ExtensionCache* temp = g_extension_cache_override;
-  g_extension_cache_override = cache;
-  return temp;
-}
-
-}  // namespace extensions