Implement out-of-process proxy for PPB_Buffer_Dev.

ppapi/thunk/ppb_buffer_trusted_thunk.cc

Index: ppapi/thunk/ppb_buffer_trusted_thunk.cc
diff --git a/ppapi/thunk/ppb_buffer_trusted_thunk.cc b/ppapi/thunk/ppb_buffer_trusted_thunk.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f20d6d584a1f4a27fb02e3a9b0488bf999b9ddcf
--- /dev/null
+++ b/ppapi/thunk/ppb_buffer_trusted_thunk.cc
@@ -0,0 +1,34 @@
+// Copyright (c) 2011 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 "ppapi/c/pp_errors.h"
+#include "ppapi/thunk/thunk.h"
+#include "ppapi/thunk/enter.h"
+#include "ppapi/thunk/ppb_buffer_trusted_api.h"
+#include "ppapi/thunk/resource_creation_api.h"
+
+namespace ppapi {
+namespace thunk {
+
+namespace {
+
+int32_t GetSharedMemory(PP_Resource buffer_id, int* shm_handle) {
+  EnterResource<PPB_BufferTrusted_API> enter(buffer_id, true);
+  if (enter.failed())
+    return PP_ERROR_BADRESOURCE;
+  return enter.object()->GetSharedMemory(shm_handle);
+}
+
+const PPB_BufferTrusted g_ppb_buffer_trusted_thunk = {
+  &GetSharedMemory,
+};
+
+}  // namespace
+
+const PPB_BufferTrusted* GetPPB_BufferTrusted_Thunk() {
+  return &g_ppb_buffer_trusted_thunk;
+}
+
+}  // namespace thunk
+}  // namespace ppapi