[SharedArrayBuffer] Prevent SharedArrayBuffer being used in Web APIs

third_party/WebKit/Source/bindings/core/v8/V8Binding.h

Index: third_party/WebKit/Source/bindings/core/v8/V8Binding.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8Binding.h b/third_party/WebKit/Source/bindings/core/v8/V8Binding.h
index 81b839e5862974baf9cb0b5b6aac647a29e9b3a4..cdb8907ab5c828b0ee1f9d5c1a0e2da54f694e34 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8Binding.h
+++ b/third_party/WebKit/Source/bindings/core/v8/V8Binding.h
@@ -47,6 +47,7 @@
 #include "bindings/core/v8/V8ThrowException.h"
 #include "bindings/core/v8/V8ValueCache.h"
 #include "core/CoreExport.h"
+#include "core/dom/NotShared.h"
 #include "platform/heap/Handle.h"
 #include "v8/include/v8.h"
 #include "wtf/text/AtomicString.h"
@@ -1152,6 +1153,23 @@ CORE_EXPORT v8::Local<v8::Value> freezeV8Object(v8::Local<v8::Value>,
 CORE_EXPORT v8::Local<v8::Value> fromJSONString(v8::Isolate*,
                                                 const String& stringifiedJSON,
                                                 ExceptionState&);
+
+// TODO(binji) : document
+template <typename NotSharedType>
+CORE_EXPORT NotSharedType toNotShared(v8::Isolate* isolate,
+                                      v8::Local<v8::Value> value,
+                                      ExceptionState& exceptionState) {
+  using DOMTypedArray = typename NotSharedType::TypedArrayType;
+  DOMTypedArray* domTypedArray =
+      V8TypeOf<DOMTypedArray>::Type::toImplWithTypeCheck(isolate, value);
+  if (domTypedArray->isShared()) {
+    exceptionState.throwTypeError(
+        "The provided ArrayBufferView value must not be shared.");
+    return NotSharedType();
+  }
+  return NotSharedType(domTypedArray);
+}
+
 }  // namespace blink
 
 #endif  // V8Binding_h