ImageData.runtimeType has changed in Dartium

[kmillikin]

With d9f80a9 the implementation class of the (abstract) dart:typed_data class Uint8ClampedList changed to _Uint8ClampedList.

It is still intended to report 'Uint8ClampedList' from .runtimeType.toString(). For some reason I don't yet understand, this doesn't happen in Dartium which reports '_Uint8ClampedList'.

[fsc8000]

Type.toString does not always use the class name. e.g. runtimeType of 42 is not _Smi, but int. See UserVisibleName in object.cc.

You need to make sure that Class::UserVisibleName returns the correct string - Uint8ClampedList in this case.