In SVGResourceCache::clientStyleChanged we return early if diff == StyleDifference::Equal.  But we can have StyleDifference::Equal even when the filter property has changed: specifically, when the element does not have a layer, RenderElement::adjustStyleDifference declines to set any new diff value.

The result of this is that changes to the filter property are sometimes not acted upon.

We can fix this by removing the early exit or by introducing a new StyleDifference value to use when the filter property changes and there is no layer.