[Mojo] Improve JavaScript API for MojoReadMessage

gin/converter.cc

 // Copyright 2013 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 "gin/converter.h"
 
 #include "v8/include/v8.h"
 
+using v8::ArrayBuffer;
 using v8::Boolean;
 using v8::External;
 using v8::Function;
 using v8::Handle;
 using v8::Integer;
 using v8::Isolate;
 using v8::Number;
 using v8::Object;
 using v8::String;
 using v8::Value;
@@ skipping 99 matching lines @@
 }
 
 bool Converter<Handle<Object> >::FromV8(Handle<Value> val,
                                         Handle<Object>* out) {
   if (!val->IsObject())
     return false;
   *out = Handle<Object>::Cast(val);
   return true;
 }
 
+Handle<Value> Converter<Handle<ArrayBuffer> >::ToV8(v8::Isolate* isolate,
+                                                    Handle<ArrayBuffer> val) {
+  return val.As<Value>();
+}
+
+bool Converter<Handle<ArrayBuffer> >::FromV8(Handle<Value> val,
+                                             Handle<ArrayBuffer>* out) {
+  if (!val->IsArrayBuffer())
+    return false;
+  *out = Handle<ArrayBuffer>::Cast(val);
+  return true;
+}
+
 Handle<Value> Converter<Handle<External> >::ToV8(v8::Isolate* isolate,
                                                  Handle<External> val) {
   return val.As<Value>();
 }
 
 bool Converter<Handle<External> >::FromV8(Handle<Value> val,
                                           Handle<External>* out) {
   if (!val->IsExternal())
     return false;
   *out = Handle<External>::Cast(val);
@@ skipping 14 matching lines @@
 v8::Handle<v8::String> StringToSymbol(v8::Isolate* isolate,
                                       const std::string& val) {
   return String::NewFromUtf8(isolate,
                              val.data(),
                              String::kInternalizedString,
                              static_cast<uint32_t>(val.length()));
 }
 
 
 }  // namespace gin