Cleanup dart to string conversions.

Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp

Index: Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp
diff --git a/Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp b/Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp
index bf5598db75beb3581a1172b8bcec657704f2c6fe..14a7fcaf7cfca04013e138b841b8a35bc30ad3ec 100644
--- a/Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp
+++ b/Source/WebCore/bindings/dart/custom/DartDOMWindowCustom.cpp
@@ -98,11 +98,9 @@ void locationSetter(Dart_NativeArguments args)
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
         ASSERT(receiver == DartUtilities::domWindowForCurrentIsolate());
 
-        const ParameterAdapter<String> location(Dart_GetNativeArgument(args, 1));
-        if (!location.conversionSuccessful()) {
-            exception = location.exception();
+        DartStringAdapter location = DartUtilities::dartToString(Dart_GetNativeArgument(args, 1), exception);
+        if (exception)
             goto fail;
-        }
 
         receiver->setLocation(location, receiver, receiver);
         return;
@@ -121,21 +119,15 @@ void openCallback(Dart_NativeArguments args)
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
         ASSERT(receiver == DartUtilities::domWindowForCurrentIsolate());
 
-        const ParameterAdapter<String> url(Dart_GetNativeArgument(args, 1));
-        if (!url.conversionSuccessful()) {
-            exception = url.exception();
+        DartStringAdapter url = DartUtilities::dartToString(Dart_GetNativeArgument(args, 1), exception);
+        if (exception)
             goto fail;
-        }
-        const ParameterAdapter<String> name(Dart_GetNativeArgument(args, 2));
-        if (!name.conversionSuccessful()) {
-            exception = name.exception();
+        DartStringAdapter name = DartUtilities::dartToString(Dart_GetNativeArgument(args, 2), exception);
+        if (exception)
             goto fail;
-        }
-        const ParameterAdapter<String> options(Dart_GetNativeArgument(args, 3), DartUtilities::ConvertNullToDefaultValue);
-        if (!options.conversionSuccessful()) {
-            exception = options.exception();
+        DartStringAdapter options = DartUtilities::dartToStringWithNullCheck(Dart_GetNativeArgument(args, 3), exception);
+        if (exception)
             goto fail;
-        }
 
         RefPtr<DOMWindow> openedWindow = receiver->open(url, name, options, receiver, receiver);
         if (openedWindow)
@@ -181,11 +173,9 @@ void handlePostMessageCallback(Dart_NativeArguments args, bool extendedTransfer)
         if (exception)
             goto fail;
 
-        const ParameterAdapter<String> targetOrigin(Dart_GetNativeArgument(args, 2));
-        if (!targetOrigin.conversionSuccessful()) {
-            exception = targetOrigin.exception();
+        DartStringAdapter targetOrigin = DartUtilities::dartToString(Dart_GetNativeArgument(args, 2), exception);
+        if (exception)
             goto fail;
-        }
 
         ExceptionCode ec = 0;
         receiver->postMessage(message.release(), &portArray, targetOrigin, source, ec);
@@ -262,11 +252,9 @@ void addEventListenerCallback(Dart_NativeArguments args)
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
         ASSERT(receiver == DartUtilities::domWindowForCurrentIsolate());
 
-        const ParameterAdapter<String> type(Dart_GetNativeArgument(args, 1));
-        if (!type.conversionSuccessful()) {
-            exception = type.exception();
+        DartStringAdapter type = DartUtilities::dartToString(Dart_GetNativeArgument(args, 1), exception);
+        if (exception)
             goto fail;
-        }
         EventListener* listener = DartEventListener::toNative(Dart_GetNativeArgument(args, 2), exception);
         if (exception)
             goto fail;
@@ -291,11 +279,9 @@ void removeEventListenerCallback(Dart_NativeArguments args)
         DOMWindow* receiver = DartDOMWrapper::receiver<DOMWindow>(args);
         ASSERT(receiver == DartUtilities::domWindowForCurrentIsolate());
 
-        const ParameterAdapter<String> type(Dart_GetNativeArgument(args, 1));
-        if (!type.conversionSuccessful()) {
-            exception = type.exception();
+        DartStringAdapter type = DartUtilities::dartToString(Dart_GetNativeArgument(args, 1), exception);
+        if (exception)
             goto fail;
-        }
         EventListener* listener = DartEventListener::toNative(Dart_GetNativeArgument(args, 2), exception);
         if (exception)
             goto fail;