Removes abuse of createClosure() from ScriptPromiseTest.

third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp

Index: third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp b/third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp
index 285f8739a411c904656d95c5e73a37086c5e3b87..41a0d7940f5fe4cfcabad5f9aa748c5755346680 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/V8BindingForTesting.cpp
@@ -82,6 +82,11 @@ Document& V8TestingScope::document()
 
 V8TestingScope::~V8TestingScope()
 {
+    // TODO(yukishiino): We put this statement here to clear an exception from
+    // the isolate.  Otherwise, the leak detector complains.  Really mysterious
+    // hack.
+    v8::Function::New(context(), nullptr);
+
     if (m_holder->document().frame())
         getScriptState()->disposePerContextData();
 }