Docs plus removing some junk per API review.

Change-Id: I45f995b656754550be68c78e467071d6e59b348f
diff --git a/graphics/java/android/renderscript/ProgramVertex.java b/graphics/java/android/renderscript/ProgramVertex.java
index 7ba8b82..a965b81 100644
--- a/graphics/java/android/renderscript/ProgramVertex.java
+++ b/graphics/java/android/renderscript/ProgramVertex.java
@@ -46,7 +46,7 @@
         /**
          * Create a builder object.
          *
-         * @param rs
+         * @param rs Context to which the program will belong.
          */
         public Builder(RenderScript rs) {
             super(rs);