[Extensions] Pull ExtensionId into its own file

extensions/browser/value_store/value_store_factory_impl.h

 // Copyright 2016 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.
 
 #ifndef EXTENSIONS_BROWSER_VALUE_STORE_VALUE_STORE_FACTORY_IMPL_H_
 #define EXTENSIONS_BROWSER_VALUE_STORE_VALUE_STORE_FACTORY_IMPL_H_
 
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "extensions/browser/value_store/value_store.h"
 #include "extensions/browser/value_store/value_store_factory.h"
-#include "extensions/common/extension.h"
+#include "extensions/common/extension_id.h"
 
 namespace extensions {
 
 class LegacyValueStoreFactory;
 
 // Mint new |ValueStore| instances for use by the extensions system. These are
 // used for extension rules, state, and settings.
 class ValueStoreFactoryImpl : public ValueStoreFactory {
  public:
   explicit ValueStoreFactoryImpl(const base::FilePath& profile_path);
@@ skipping 20 matching lines @@
   ~ValueStoreFactoryImpl() override;
 
   scoped_refptr<LegacyValueStoreFactory> legacy_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ValueStoreFactoryImpl);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_VALUE_STORE_VALUE_STORE_FACTORY_IMPL_H_