Added tests for smooth and noSmooth for preproc.

In response to https://github.com/processing/processing4/issues/149,
adding tests to catch issues with smooth and noSmooth in the
preprocessor. Issue found by @benfry.

java/test/processing/mode/java/ParserTests.java

@@ -365,4 +365,19 @@ public class ParserTests {
     expectGood("colorreturn");
   }
 
+  @Test
+  public void testNoSmooth() {
+    expectGood("nosmooth");
+  }
+
+  @Test
+  public void testSmooth() {
+    expectGood("smoothnoparam");
+  }
+
+  @Test
+  public void testSmoothWithParam() {
+    expectGood("smoothparam");
+  }
+
 }