Revert "Animate shade blur fallback"

This reverts commit e0677abe.

Reason for revert: Previously there was a bug so the blur isn't turned off when fallback happens. Now with blur turned off, the transparency doesn't get opaque until much later, causing everything to be seen through. With the animation, it makes things worse. Unless we find a better solution, let's revert this for now.

Bug: 388891313
Change-Id: I479c29cb95e4bb4cd182d996c4dcd06df051d851