Remove deprecated StringBuffer.add, addAll and addCharCode.

editor/tools/plugins/com.google.dart.tools.core_test/src/com/google/dart/tools/core/formatter/testsource/test007$A_out.dart

 /*
  * this is a test class
  */
 class Version {
   int major;
   int minor;
   int service;
   String qualifier;
   
   Version.full(int this.major, int this.minor, int this.service, String this.qualifier);
   Version.part(major, minor, service):this.full(major, minor, service, null);
   
   String toString() {
     StringBuffer sb = new StringBuffer();
-    sb.add(this.major).add('.').
-       add(this.minor).add('.').
-       add(service).add('.').
-       add(this.qualifier);
+    sb..write(this.major)..write('.').
+      ..write(this.minor)..write('.').
+      ..write(service)..write('.').
+      ..write(this.qualifier);
     return sb.toString(); 
   }
 }