Close leaking FDs.

content/public/browser/content_browser_client.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_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 #define CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 432 matching lines @@
   // Returns true if renderer processes can use Pepper TCP/UDP sockets from
   // the given origin.
   virtual bool AllowPepperSocketAPI(BrowserContext* browser_context,
                                     const GURL& url);
 
   // Returns true if renderer processes can use private Pepper File APIs.
   virtual bool AllowPepperPrivateFileAPI();
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   // Populates |mappings| with all files that need to be mapped before launching
-  // a child process.
+  // a child process.  Note that the caller takes ownership of the file
+  // descriptors returned in mappings, meaning you should not close them after
+  // that call and you must dup them if you need to use them after this method
+  // is called.
   virtual void GetAdditionalMappedFilesForChildProcess(
       const CommandLine& command_line,
       base::GlobalDescriptors::Mapping* mappings) {}
 #endif
 
 #if defined(OS_WIN)
   // Returns the name of the dll that contains cursors and other resources.
   virtual const wchar_t* GetResourceDllName();
 #endif
 
 #if defined(USE_NSS)
   // Return a delegate to authenticate and unlock |module|.
   // This is called on a worker thread.
   virtual
       crypto::CryptoModuleBlockingPasswordDelegate* GetCryptoPasswordDelegate(
           const GURL& url);
 #endif
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_