Fix FloatingActionButton show() animation

If show() is called while the hide() animation is
currently happening then the show() call is ignored.
This CL fixes that by making sure that we cancel
any on-going animation and ensure we honor the show().

BUG: 22813854
Change-Id: I4ed758dfc9e1203a97e32ccf0f07f64a0c2a2a71
1 file changed