Add toImplSequence()

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

Index: third_party/WebKit/Source/bindings/core/v8/V8Binding.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8Binding.cpp b/third_party/WebKit/Source/bindings/core/v8/V8Binding.cpp
index d0bb9de194cf24ec8ad2487adc5c89c2ed997404..64c806effb0e00657aa309f18873126eba93e42f 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8Binding.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/V8Binding.cpp
@@ -905,6 +905,28 @@ v8::Local<v8::Function> getBoundFunction(v8::Local<v8::Function> function)
     return boundFunction->IsFunction() ? v8::Local<v8::Function>::Cast(boundFunction) : function;
 }
 
+v8::MaybeLocal<v8::Object> getEsIterator(v8::Isolate* isolate, v8::Local<v8::Object> object, ExceptionState& exceptionState)
+{
+    v8::Local<v8::Context> context = isolate->GetCurrentContext();
+    v8::Local<v8::Value> iteratorGetter;
+    if (!object->Get(context, v8::Symbol::GetIterator(isolate)).ToLocal(&iteratorGetter))
+        return v8::MaybeLocal<v8::Object>();
+    if (!iteratorGetter->IsFunction()) {
+        exceptionState.throwTypeError("Iterator getter is not callable.");
+        return v8::MaybeLocal<v8::Object>();
+    }
+
+    v8::Local<v8::Function> getterFunction = iteratorGetter.As<v8::Function>();
+    v8::Local<v8::Value> iterator;
+    if (!V8ScriptRunner::callFunction(getterFunction, toExecutionContext(context), object, 0, nullptr, isolate).ToLocal(&iterator))
+        return v8::MaybeLocal<v8::Object>();
+    if (!iterator->IsObject()) {
+        exceptionState.throwTypeError("Iterator is not an object.");
+        return v8::MaybeLocal<v8::Object>();
+    }
+    return v8::MaybeLocal<v8::Object>(iterator.As<v8::Object>());
+}
+
 bool addHiddenValueToArray(v8::Isolate* isolate, v8::Local<v8::Object> object, v8::Local<v8::Value> value, int arrayIndex)
 {
     ASSERT(!value.IsEmpty());