fixes #610, incorrect help output

tool/build_test_pkgs.sh

Index: tool/build_test_pkgs.sh
diff --git a/tool/build_test_pkgs.sh b/tool/build_test_pkgs.sh
index 1e45949945739844a04e44fe13eb8e3ab1013e0d..c02712ce537bb17887e818fb1bcc7a24a9877bd2 100755
--- a/tool/build_test_pkgs.sh
+++ b/tool/build_test_pkgs.sh
@@ -11,23 +11,24 @@ SDK=--dart-sdk-summary=lib/runtime/dart_sdk.sum
     --url-mapping=package:expect/expect.dart,test/codegen/expect.dart \
     package:expect/expect.dart
 
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/async_helper.js \
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/async_helper.js \
     --url-mapping=package:async_helper/async_helper.dart,test/codegen/async_helper.dart \
     package:async_helper/async_helper.dart
 
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/js.js \
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/js.js \
     package:js/js.dart
 
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/matcher.js \
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/matcher.js \
     package:matcher/matcher.dart
 
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/stack_trace.js \
-    package:stack_trace/stack_trace.dart
-
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/path.js \
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/path.js \
     package:path/path.dart
 
-./bin/dartdevc.dart $SDK  -o gen/codegen_output/pkg/unittest.js \
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/stack_trace.js \
+    -s gen/codegen_output/pkg/path.sum \
+    package:stack_trace/stack_trace.dart
+
+./bin/dartdevc.dart $SDK -o gen/codegen_output/pkg/unittest.js \
     package:unittest/unittest.dart \
     package:unittest/html_config.dart \
     package:unittest/html_individual_config.dart \