Enable size_t to int truncation warnings in PPAPI

ppapi/proxy/flash_clipboard_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/flash_clipboard_resource.h"
 
+#include "base/numerics/safe_conversions.h"
 #include "ipc/ipc_message.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
 #include "ppapi/shared_impl/var.h"
 #include "ppapi/shared_impl/var_tracker.h"
 
 namespace ppapi {
 namespace proxy {
 
@@ skipping 29 matching lines @@
 }
 
 PP_Var ClipboardStringToPPVar(int32_t format,
                               const std::string& string) {
   if (format == PP_FLASH_CLIPBOARD_FORMAT_PLAINTEXT ||
       format == PP_FLASH_CLIPBOARD_FORMAT_HTML) {
     return StringVar::StringToPPVar(string);
   } else {
     // All other formats are expected to be array buffers.
     return PpapiGlobals::Get()->GetVarTracker()->MakeArrayBufferPPVar(
-        string.size(), string.data());
+        base::checked_cast<uint32_t>(string.size()), string.data());
   }
 }
 }  // namespace
 
 FlashClipboardResource::FlashClipboardResource(
     Connection connection, PP_Instance instance)
     : PluginResource(connection, instance) {
   SendCreate(BROWSER, PpapiHostMsg_FlashClipboard_Create());
 }
 
@@ skipping 92 matching lines @@
   int32_t result =
       SyncCall<PpapiPluginMsg_FlashClipboard_GetSequenceNumberReply>(
           BROWSER,
           PpapiHostMsg_FlashClipboard_GetSequenceNumber(clipboard_type),
           sequence_number);
   return PP_FromBool(result == PP_OK);
 }
 
 }  // namespace proxy
 }  // namespace ppapi