[Sync] Convert sync to a static library.

components/sync/js/js_event_handler.h

 // Copyright 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.
 
 #ifndef COMPONENTS_SYNC_JS_JS_EVENT_HANDLER_H_
 #define COMPONENTS_SYNC_JS_JS_EVENT_HANDLER_H_
 
 // See README.js for design comments.
 
 #include <string>
 
-#include "components/sync/base/sync_export.h"
-
 namespace syncer {
 
 class JsEventDetails;
 
 // An interface for objects that handle Javascript events (e.g.,
 // WebUIs).
-class SYNC_EXPORT JsEventHandler {
+class JsEventHandler {
  public:
   virtual void HandleJsEvent(const std::string& name,
                              const JsEventDetails& details) = 0;
 
  protected:
   virtual ~JsEventHandler() {}
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_JS_JS_EVENT_HANDLER_H_