implement a few methods to make SWT 3.4 happy

classpath/java/lang/StringBuilder.java

@@ -154,6 +154,10 @@ public class StringBuilder implements CharSequence {
     return insert(i, new String(new char[] { c }, 0, 1, false));
   }
 
+  public StringBuilder insert(int i, int v) {
+    return insert(i, String.valueOf(v));
+  }
+
   public StringBuilder delete(int start, int end) {
     if (start >= end) {
       return this;