Allow for accessing an ArrayBuffer contents without externalizing it

test/cctest/test-typedarrays.cc

 // Copyright 2015 the V8 project 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 <stdlib.h>
 
 #include "src/v8.h"
 #include "test/cctest/cctest.h"
 
 #include "src/api.h"
 #include "src/heap/heap.h"
 #include "src/objects.h"
+#include "src/v8.h"
 
 using namespace v8::internal;
 
 void TestArrayBufferViewContents(LocalContext& env, bool should_use_buffer) {
   v8::Local<v8::Object> obj_a =
       v8::Local<v8::Object>::Cast(env->Global()->Get(v8_str("a")));
   CHECK(obj_a->IsArrayBufferView());
   v8::Local<v8::ArrayBufferView> array_buffer_view =
       v8::Local<v8::ArrayBufferView>::Cast(obj_a);
   CHECK_EQ(array_buffer_view->HasBuffer(), should_use_buffer);
@@ skipping 36 matching lines @@
       "var c = new Uint8Array(b);"
       "c[0] = -1;"
       "c[1] = -1;"
       "c[2] = 0;"
       "c[3] = 1;"
       "c[4] = 2;"
       "c[5] = 3;"
       "var a = new DataView(b, 2);");
   TestArrayBufferViewContents(env, true);
 }
+
+
+TEST(AllocateNotExternal) {
+  LocalContext env;
+  v8::HandleScope scope(env->GetIsolate());
+  void* memory = V8::ArrayBufferAllocator()->Allocate(1024);
+  v8::Local<v8::ArrayBuffer> buffer =
+      v8::ArrayBuffer::New(env->GetIsolate(), memory, 1024, false);
+  CHECK(!buffer->IsExternal());
+  CHECK_EQ(memory, buffer->GetContents().Data());
+}