Enable anti-aliasing for clip-path in vector drawables.

I definitely do not know what I'm doing here, so please view with
skepticism. I don't know how to check if there are other similar calls
that should be updated.

To test this I changed the Lens icon in NexusLauncher to use clip-path.
You can see the diff here: https://screenshot.googleplex.com/AoXzx2iojWQSS9v

Bug: 200304852
Change-Id: I482920c3449fa9e89906b46631b44e6264a46e61