make base::SharedMemoryHandle a class on POSIX.

mojo/public/cpp/system/platform_handle.cc

 // Copyright 2016 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.
 
 #include "mojo/public/cpp/system/platform_handle.h"
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
 #include <mach/mach.h>
 #include "base/mac/mach_logging.h"
 #endif
@@ skipping 48 matching lines @@
     *file = PlatformFileFromPlatformHandleValue(platform_handle.value);
   }
 
   return MOJO_RESULT_OK;
 }
 
 ScopedSharedBufferHandle WrapSharedMemoryHandle(
     const base::SharedMemoryHandle& memory_handle,
     size_t size,
     bool read_only) {
-#if defined(OS_POSIX) && !(defined(OS_MACOSX) && !defined(OS_IOS))
-  if (memory_handle.fd == base::kInvalidPlatformFile)
-    return ScopedSharedBufferHandle();
-#else
   if (!memory_handle.IsValid())
     return ScopedSharedBufferHandle();
-#endif
   MojoPlatformHandle platform_handle;
   platform_handle.struct_size = sizeof(MojoPlatformHandle);
   platform_handle.type = kPlatformSharedBufferHandleType;
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   platform_handle.value =
       static_cast<uint64_t>(memory_handle.GetMemoryObject());
-#elif defined(OS_POSIX)
-  platform_handle.value = PlatformHandleValueFromPlatformFile(memory_handle.fd);
-#elif defined(OS_WIN)
+#else
   platform_handle.value =
       PlatformHandleValueFromPlatformFile(memory_handle.GetHandle());
 #endif
 
   MojoPlatformSharedBufferHandleFlags flags =
       MOJO_PLATFORM_SHARED_BUFFER_HANDLE_FLAG_NONE;
   if (read_only)
     flags |= MOJO_PLATFORM_SHARED_BUFFER_HANDLE_FLAG_READ_ONLY;
 
   MojoHandle mojo_handle;
@@ skipping 27 matching lines @@
     *read_only = flags & MOJO_PLATFORM_SHARED_BUFFER_HANDLE_FLAG_READ_ONLY;
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   CHECK_EQ(platform_handle.type, MOJO_PLATFORM_HANDLE_TYPE_MACH_PORT);
   *memory_handle = base::SharedMemoryHandle(
       static_cast<mach_port_t>(platform_handle.value), num_bytes,
       base::GetCurrentProcId());
 #elif defined(OS_POSIX)
   CHECK_EQ(platform_handle.type, MOJO_PLATFORM_HANDLE_TYPE_FILE_DESCRIPTOR);
   *memory_handle = base::SharedMemoryHandle(
-      static_cast<int>(platform_handle.value), false);
+      base::FileDescriptor(static_cast<int>(platform_handle.value), false));
 #elif defined(OS_WIN)
   CHECK_EQ(platform_handle.type, MOJO_PLATFORM_HANDLE_TYPE_WINDOWS_HANDLE);
   *memory_handle = base::SharedMemoryHandle(
       reinterpret_cast<HANDLE>(platform_handle.value),
       base::GetCurrentProcId());
 #endif
 
   return MOJO_RESULT_OK;
 }
 
@@ skipping 26 matching lines @@
   if (result != MOJO_RESULT_OK)
     return result;
 
   CHECK_EQ(platform_handle.type, MOJO_PLATFORM_HANDLE_TYPE_MACH_PORT);
   *port = static_cast<mach_port_t>(platform_handle.value);
   return MOJO_RESULT_OK;
 }
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 
 }  // namespace mojo