Remove base::SharedMemory::ShareToProcess.

base/memory/shared_memory_handle.h

 // Copyright 2015 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 BASE_MEMORY_SHARED_MEMORY_HANDLE_H_
 #define BASE_MEMORY_SHARED_MEMORY_HANDLE_H_
 
 #include <stddef.h>
 
 #include "build/build_config.h"
@@ skipping 38 matching lines @@
   void Close() const;
 
   // Whether ownership of the underlying OS resource is implicitly passed to
   // the IPC subsystem during serialization.
   void SetOwnershipPassesToIPC(bool ownership_passes);
   bool OwnershipPassesToIPC() const;
 
   // Whether the underlying OS resource is valid.
   bool IsValid() const;
 
-  // Duplicates the underlying OS resource.
+  // Duplicates the underlying OS resource. Using the return value as a
+  // parameter to an IPC message will cause the IPC subsystem to consume the OS

[Nico, 2017/05/02 20:08:00]

Feels like a bit strange place to document this (I'd expected this somewhere in
the IPC code), but ok :-)

+  // resource.
   SharedMemoryHandle Duplicate() const;
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   enum Type {
     // The SharedMemoryHandle is backed by a POSIX fd.
     POSIX,
     // The SharedMemoryHandle is backed by the Mach primitive "memory object".
     MACH,
   };
 
@@ skipping 109 matching lines @@
   // Defaults to |false|.
   bool ownership_passes_to_ipc_;
 #else
   FileDescriptor file_descriptor_;
 #endif
 };
 
 }  // namespace base
 
 #endif  // BASE_MEMORY_SHARED_MEMORY_HANDLE_H_