Generate param traits size methods for IPC files in chrome/ (and traits it depends on).

media/gpu/ipc/common/media_messages.h

 // 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.
 
 // Multiply-included message file, hence no include guard here, but see below
 // for a much smaller-than-usual include guard section.
 
 #include "gpu/config/gpu_info.h"
 #include "gpu/ipc/common/gpu_param_traits_macros.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/param_traits_macros.h"
 #include "media/base/bitstream_buffer.h"
 #include "media/gpu/ipc/common/media_param_traits.h"
 #include "media/video/jpeg_decode_accelerator.h"
 #include "media/video/video_decode_accelerator.h"
 #include "media/video/video_encode_accelerator.h"
 #include "ui/gfx/ipc/gfx_param_traits.h"
 
 #define IPC_MESSAGE_START MediaMsgStart
 
 #ifndef MEDIA_GPU_IPC_COMMON_MEDIA_MESSAGES_H_
 #define MEDIA_GPU_IPC_COMMON_MEDIA_MESSAGES_H_
 
 namespace IPC {
 template <>
 struct ParamTraits<media::BitstreamBuffer> {
   using param_type = media::BitstreamBuffer;
+  static void GetSize(base::PickleSizer* s, const param_type& p);
   static void Write(base::Pickle* m, const param_type& p);
   static bool Read(const base::Pickle* m,
                    base::PickleIterator* iter,
                    param_type* r);
   static void Log(const param_type& p, std::string* l);
 };
 
 }  // namespace IPC
 
 #endif  // MEDIA_GPU_IPC_COMMON_MEDIA_MESSAGES_H_
@@ skipping 192 matching lines @@
 IPC_MESSAGE_ROUTED0(AcceleratedJpegDecoderMsg_Destroy)
 
 //------------------------------------------------------------------------------
 // Accelerated JPEG Decoder Host Messages
 // These messages are sent from the GPU process to Browser process.
 //
 // Report decode status.
 IPC_MESSAGE_ROUTED2(AcceleratedJpegDecoderHostMsg_DecodeAck,
                     int32_t, /* bitstream_buffer_id */
                     media::JpegDecodeAccelerator::Error /* error */)