Added PlatformHandle thunks.

mojo/public/platform/native/platform_handle_private_thunks.c

+// 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/platform/native/platform_handle_private_thunks.h"
+
+#include "mojo/public/platform/native/thunk_export.h"
+
+#include <assert.h>
+
+static struct MojoPlatformHandlePrivateThunks g_thunks = {0};
+
+MojoResult MojoCreatePlatformHandleWrapper(MojoPlatformHandle platform_handle,
+                                           MojoHandle* wrapper) {
+  assert(g_thunks.CreatePlatformHandleWrapper);
+  return g_thunks.CreatePlatformHandleWrapper(platform_handle, wrapper);
+}
+
+MojoResult MojoExtractPlatformHandle(MojoHandle wrapper,
+                                     MojoPlatformHandle* platform_handle) {
+  assert(g_thunks.ExtractPlatformHandle);
+  return g_thunks.ExtractPlatformHandle(wrapper, platform_handle);
+}
+
+THUNK_EXPORT size_t MojoSetPlatformHandlePrivateThunks(
+    const struct MojoPlatformHandlePrivateThunks* thunks) {
+  if (thunks->size >= sizeof(g_thunks))
+    g_thunks = *thunks;
+  return sizeof(g_thunks);
+}