Fallback to unsupported browser type instead of returning null

Source/bindings/dart/DartDOMWrapper.cpp

Index: Source/bindings/dart/DartDOMWrapper.cpp
diff --git a/Source/bindings/dart/DartDOMWrapper.cpp b/Source/bindings/dart/DartDOMWrapper.cpp
index f73b9091e9978daef8fb4beadf3daee02d5e4c5e..348f47272be437b88ad80b407a334ae59604ce91 100644
--- a/Source/bindings/dart/DartDOMWrapper.cpp
+++ b/Source/bindings/dart/DartDOMWrapper.cpp
@@ -74,8 +74,12 @@ Dart_PersistentHandle DartDOMWrapper::dartClass(
         }
     }
     if ((searchid <= 0) || Dart_IsError(type) || !Dart_IsType(type) || Dart_IsNull(type)) {
-        DartUtilities::reportProblem(domData->scriptExecutionContext(), type);
-        return Dart_Null();
+        char message[256];
+        strcpy(message, "Unsupported native browser type: ");
+        strncat(message, DartWebkitClassInfo[cid].jsName, 255 - strlen(message));

[siva, 2014/08/26 19:31:14]

Why not use
snprint(message, 256, "Unsupported native browser type: %s",
DartWebkitClassInfo[cid].jsName);


Also this new error is overriding the original error that was produced by
'getType' why not do this only under
if (!Dart_IsError(type)) {
  ....
  ....
}
type = Dart_GetType(...);

[vsm, 2014/08/27 07:50:29]

Done.

+        Dart_Handle error = Dart_NewApiError(message);
+        DartUtilities::reportProblem(domData->scriptExecutionContext(), error);
+        type = Dart_GetType(htmlLibrary, Dart_NewStringFromCString("_UnsupportedBrowserObject"), 0, 0);

[siva, 2014/08/26 19:31:14]

I hope this is just a temporary solution, when we start generating
code using the actual chrome IDL instead of the way things are being
done now this should never happen right. Any error here would be more
an InternalError.

[vsm, 2014/08/27 08:05:10]

As long as we continue to push the types to user code, we do need something
defensive here.  We cannot assume we'll get a type or a valid type.

Should we also verify that this type has (at least) two native fields?  What
happens if we call Dart_AllocateWithNativeFields on some arbitrary type?

On 2014/08/26 19:31:14, siva wrote:

     }
 
     persistentType = Dart_NewPersistentHandle(type);