Add test cases

Author: odersky

tests/pickling/i4430.scala

@@ -0,0 +1,7 @@
+object Test {
+  def main(args: Array[String]): Unit = {
+    val sb = new java.lang.StringBuilder()
+    sb.append(Array[Char](), 0, 0)
+    sb.length
+  }
+}

tests/run/i4430.scala

@@ -0,0 +1,7 @@
+object Test {
+  def main(args: Array[String]): Unit = {
+    val sb = new java.lang.StringBuilder()
+    sb.append(Array[Char](), 0, 0)
+    sb.length
+  }
+}