Fix regressed alpha change in VD

BUG: 116355161
Test: cts-tradefed run commandAndExit cts -d --skip-preconditions --test android.graphics.drawable.cts.VectorDrawableTest --module CtsGraphicsTestCases

Change-Id: I4d1bc13d8544d0fc64c5457f8a70c3089a9334c1
1 file changed