Cleanup: Put more plugin code behind the ENABLE_PLUGINS ifdef.

content/common/pepper_renderer_instance_data.h

 // 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.
 
 #ifndef CONTENT_COMMON_PEPPER_RENDERER_INSTANCE_DATA_H_
 #define CONTENT_COMMON_PEPPER_RENDERER_INSTANCE_DATA_H_
 
 #include "url/gurl.h"
 
+#if !defined(ENABLE_PLUGINS)
+#error "Plugins should be enabled"
+#endif
+
 namespace content {
 
 // This struct contains data which is associated with a particular plugin
 // instance and is related to the renderer in which the plugin instance lives.
 // This data is transferred to the browser process from the renderer when the
 // instance is created and is stored in the BrowserPpapiHost.
 struct PepperRendererInstanceData {
   PepperRendererInstanceData();
   PepperRendererInstanceData(int render_process,
                              int render_frame_id,
                              const GURL& document,
                              const GURL& plugin);
   ~PepperRendererInstanceData();
   int render_process_id;
   int render_frame_id;
   GURL document_url;
   GURL plugin_url;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_PEPPER_RENDERER_INSTANCE_DATA_H_