Tweak j2d for String.indexOf(s,int) semantics.

editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart

 library java.core;
 
 import "dart:math" as math;
 import "dart:collection" show ListBase;
 
 class JavaSystem {
   static int currentTimeMillis() {
     return (new DateTime.now()).millisecondsSinceEpoch;
   }
 
@@ skipping 136 matching lines @@
         case '%': return '%';
         case 's':
           if (index >= args.length) {
             throw new MissingFormatArgumentException(match.group(0));
           }
           return args[index++].toString();
         default: return match.group(1);
       }
     });
   }
+  static int indexOf(String target, String str, int fromIndex) {
+    if (fromIndex > target.length) return -1;
+    if (fromIndex < 0) fromIndex = 0;
+    return target.indexOf(str, fromIndex);
+  }
+  static int lastIndexOf(String target, String str, int fromIndex) {
+    if (fromIndex > target.length) return -1;
+    if (fromIndex < 0) fromIndex = 0;
+    return target.lastIndexOf(str, fromIndex);
+  }
   static bool startsWithBefore(String s, String other, int start) {
     return s.indexOf(other, start) != -1;
   }
 }
 
 /**
  * Very limited printf implementation, supports only %s and %d.
  */
 String _printf(String fmt, List args) {
   StringBuffer sb = new StringBuffer();
@@ skipping 337 matching lines @@
       }
     } else if (sb.length > newLength) {
       var s = sb.toString().substring(0, newLength);
       sb = new StringBuffer(s);
     }
   }
   void clear() {
     sb = new StringBuffer();
   }
 }