Making Program*.Builder classes' setters return 'this'

This is for better correspondence with the Builder pattern.
See also: Effective Java, 2nd edition.

Change-Id: Iecccd42be49dea2ed8e4b8cc38ce96379cf3c11c

graphics/java/android/renderscript/ProgramVertex.java

@@ -47,8 +47,9 @@ public class ProgramVertex extends Program {
             mRS = rs;
         }
 
-        public void setTextureMatrixEnable(boolean enable) {
+        public Builder setTextureMatrixEnable(boolean enable) {
             mTextureMatrixEnable = enable;
+            return this;
         }
 
         public ProgramVertex create() {