Tweaks to PPB_VarArrayBuffer in preperation for taking out of Dev.

ppapi/native_client/src/shared/ppapi_proxy/object_serialize.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 "native_client/src/shared/ppapi_proxy/object_serialize.h"
 
 #include <limits>
 #include <stdio.h>
@@ skipping 113 matching lines @@
       if (AddWouldOverflow(string_length,
                            NACL_OFFSETOF(SerializedString, string_bytes))) {
         // Adding the length to the fixed portion would overflow.
         return 0;
       }
       return static_cast<uint32_t>(NACL_OFFSETOF(SerializedString, string_bytes)
                                    + string_length);
       break;
     }
     case PP_VARTYPE_ARRAY_BUFFER: {
-      uint32_t buffer_length = PPBVarArrayBufferInterface()->ByteLength(var);
+      uint32_t buffer_length = 0;
+      if (!PPBVarArrayBufferInterface()->ByteLength(var, &buffer_length))
+        return 0;
       buffer_length = RoundedStringBytes(buffer_length);
       if (AddWouldOverflow(buffer_length,
                            NACL_OFFSETOF(SerializedString, string_bytes))) {
         // Adding the length to the fixed portion would overflow.
         return 0;
       }
       return static_cast<uint32_t>(NACL_OFFSETOF(SerializedString, string_bytes)
                                    + buffer_length);
       break;
     }
@@ skipping 74 matching lines @@
                reinterpret_cast<const void*>(str),
                string_length);
         // Fill padding bytes with zeros.
         memset(reinterpret_cast<void*>(ss->string_bytes + string_length), 0,
             RoundedStringBytes(string_length) - string_length);
         element_size = NACL_OFFSETOF(SerializedString, string_bytes)
             + RoundedStringBytes(string_length);
         break;
       }
       case PP_VARTYPE_ARRAY_BUFFER: {
-        uint32_t buffer_length =
-            PPBVarArrayBufferInterface()->ByteLength(vars[i]);
+        uint32_t buffer_length = 0;
+        PPBVarArrayBufferInterface()->ByteLength(vars[i], &buffer_length);
         SerializedString* ss = reinterpret_cast<SerializedString*>(p);
         ss->fixed.u.string_length = buffer_length;
         memcpy(reinterpret_cast<void*>(ss->string_bytes),
                PPBVarArrayBufferInterface()->Map(vars[i]),
                buffer_length);
         // Fill padding bytes with zeros.
         memset(reinterpret_cast<void*>(ss->string_bytes + buffer_length), 0,
                RoundedStringBytes(buffer_length) - buffer_length);
         element_size = NACL_OFFSETOF(SerializedString, string_bytes)
             + RoundedStringBytes(buffer_length);
@@ skipping 272 matching lines @@
     return false;
   }
   // Read the serialized PP_Vars into the allocated memory.
   if (!DeserializePpVar(bytes, length, vars, argc)) {
     return false;
   }
   return true;
 }
 
 }  // namespace ppapi_proxy