View calls like "attachedToWindow" and "detachedToWindow" can be called
off of the main thread, on "android.anim" this happens in the system
process for application splash screens.
Let's wrap it with a synchronized block.
Fix: 124110476
Test: The crash is a race condition, so the best I can do is make sure
it generally doesn't crash anything by trying out both normal and
virtual hierarchies in Talkback.
Change-Id: I19f972a97b5ac80917f8dd77ac79bf7e3d5e826c
1aa9da4250