Potential unblur of inputs in optimization mode

[getvictor]

In optimization mode, when there are multiple items to be blurred under one grandparent, we may unblur the grandparent by mistake if one item no longer needs to be blurred.

This issue has been handled for normal nodes via processNodeWithParent function and the set of blurredElements.

But we need to think whether an issue for inputs still exists.

Need to create a test case for this:

grandparent
  -> parent1 -> blur1
  -> parent2 -> blur2