Cleanup dart to string conversions.

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

Index: Source/WebCore/bindings/dart/custom/DartIntentCustom.cpp
diff --git a/Source/WebCore/bindings/dart/custom/DartIntentCustom.cpp b/Source/WebCore/bindings/dart/custom/DartIntentCustom.cpp
index 9a4e89e39b3721c149ae8bbeddf4352410c48bbb..53f702bdaa9b9cb6aac16712051a6d1211c51df9 100644
--- a/Source/WebCore/bindings/dart/custom/DartIntentCustom.cpp
+++ b/Source/WebCore/bindings/dart/custom/DartIntentCustom.cpp
@@ -42,17 +42,13 @@ void constructorCallback(Dart_NativeArguments args)
     DartApiScope dartApiScope;
     Dart_Handle exception = 0;
     {
-        const ParameterAdapter<String> action(Dart_GetNativeArgument(args, 0));
-        if (!action.conversionSuccessful()) {
-            exception = action.exception();
+        DartStringAdapter action = DartUtilities::dartToString(Dart_GetNativeArgument(args, 0), exception);
+        if (exception)
             goto fail;
-        }
 
-        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;
-        }
 
         RefPtr<SerializedScriptValue> data;
         if (!Dart_IsNull(Dart_GetNativeArgument(args, 2))) {