Add --time option to dart test scripts.

tools/test.dart

Index: tools/test.dart
diff --git a/tools/test.dart b/tools/test.dart
index cf4fe84c5487dda08e1546dfbc14d9c4f4f957e0..2af00c8f257074b53e5642c167d96c38b4752ab3 100755
--- a/tools/test.dart
+++ b/tools/test.dart
@@ -36,6 +36,7 @@ main() {
   var maxProcesses = firstConf['tasks'];
   var progressIndicator = firstConf['progress'];
   var verbose = firstConf['verbose'];
+  var printTiming = firstConf['time'];
 
   var configurationIterator = configurations.iterator();
   bool enqueueConfiguration(ProcessQueue queue) {
@@ -98,5 +99,6 @@ main() {
                                progressIndicator,
                                verbose,
                                startTime,
+                               printTiming,
                                enqueueConfiguration);
 }