This change detects empty quads in 9patches and removes them from the mesh to avoid unnecessary blending. Change-Id: I4500566fb4cb6845d64dcb59b522c0be7a0ec704
Change-Id: I210ffa8f1d76a102bb7d971c649c20a74d03fbe6
Change-Id: I5ff864a361db4791bd5ff6be716f7ce692ef572d