Enable size_t to int truncation warnings in PPAPI

ppapi/proxy/audio_input_resource.cc

 // Copyright (c) 2012 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/proxy/audio_input_resource.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
 #include "ipc/ipc_platform_file.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_bus.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/resource_message_params.h"
 #include "ppapi/proxy/serialized_handle.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
 #include "ppapi/shared_impl/ppb_audio_config_shared.h"
 #include "ppapi/shared_impl/resource_tracker.h"
@@ skipping 223 matching lines @@
     audio_input_thread_.reset();
   }
 }
 
 void AudioInputResource::Run() {
   // The shared memory represents AudioInputBufferParameters and the actual data
   // buffer stored as an audio bus.
   media::AudioInputBuffer* buffer =
       static_cast<media::AudioInputBuffer*>(shared_memory_->memory());
   const uint32_t audio_bus_size_bytes =
-      shared_memory_size_ - sizeof(media::AudioInputBufferParameters);
+      base::checked_cast<uint32_t>(shared_memory_size_ -
+                                   sizeof(media::AudioInputBufferParameters));
 
   while (true) {
     int pending_data = 0;
     size_t bytes_read = socket_->Receive(&pending_data, sizeof(pending_data));
     if (bytes_read != sizeof(pending_data)) {
       DCHECK_EQ(bytes_read, 0U);
       break;
     }
     if (pending_data < 0)
       break;
@@ skipping 66 matching lines @@
       device_id, enter_config.object()->GetSampleRate(),
       enter_config.object()->GetSampleFrameCount());
   Call<PpapiPluginMsg_AudioInput_OpenReply>(
       RENDERER, msg,
       base::Bind(&AudioInputResource::OnPluginMsgOpenReply,
                  base::Unretained(this)));
   return PP_OK_COMPLETIONPENDING;
 }
 }  // namespace proxy
 }  // namespace ppapi