Add safari cache clearing browser functionality to the safari browser.

tools/test.dart

Index: tools/test.dart
===================================================================
--- tools/test.dart	(revision 24136)
+++ tools/test.dart	(working copy)
@@ -27,6 +27,7 @@
 import "dart:async";
 import "dart:io";
 import "dart:math" as math;
+import "testing/dart/browser_controller.dart";
 import "testing/dart/http_server.dart";
 import "testing/dart/record_and_replay.dart";
 import "testing/dart/test_options.dart";
@@ -92,6 +93,10 @@
   var recordingPath = firstConf['record_to_file'];
   var recordingOutputPath = firstConf['replay_from_file'];
 
+  // We set a special flag in the safari browser if we need to clear out
+  // the cache before running.
+  Safari.deleteCache = firstConf['clear_safari_cache'];
+
   if (recordingPath != null && recordingOutputPath != null) {
     print("Fatal: Can't have the '--record_to_file' and '--replay_from_file'"
           "at the same time. Exiting ...");
@@ -244,7 +249,6 @@
   }
   eventListener.add(new ExitCodeSetter());
 
-
   void startProcessQueue() {
     // Start process queue.
     new ProcessQueue(maxProcesses,