Pass implementation object to supplemental classes by reference

Source/web/LocalFileSystemClient.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 36 matching lines @@
 {
     return adoptPtr(static_cast<FileSystemClient*>(new LocalFileSystemClient()));
 }
 
 LocalFileSystemClient::~LocalFileSystemClient()
 {
 }
 
 bool LocalFileSystemClient::allowFileSystem(ExecutionContext* context)
 {
+    ASSERT(context);
     if (context->isDocument()) {
         Document* document = toDocument(context);
         WebFrameImpl* webFrame = WebFrameImpl::fromFrame(document->frame());
         return !webFrame->permissionClient() || webFrame->permissionClient()->allowFileSystem(webFrame);
     }
     ASSERT(context->isWorkerGlobalScope());
-    return WorkerPermissionClient::from(toWorkerGlobalScope(context))->allowFileSystem();
+    return WorkerPermissionClient::from(*toWorkerGlobalScope(context))->allowFileSystem();
 }
 
 LocalFileSystemClient::LocalFileSystemClient()
 {
 }
 
 } // namespace blink