[Swarming] Only try to untar test262 on swarming.

test/test262/testcfg.py

Index: test/test262/testcfg.py
diff --git a/test/test262/testcfg.py b/test/test262/testcfg.py
index b5ad30949d8c3ae337128bfb17f47180fc34a8d0..9da8f4efa4b5548783cd0a9433bd794acca21002 100644
--- a/test/test262/testcfg.py
+++ b/test/test262/testcfg.py
@@ -201,10 +201,13 @@ class Test262TestSuite(testsuite.TestSuite):
       for f in archive_files:
         os.remove(os.path.join(self.root, f))
 
-    print "Extracting archive..."
-    tar = tarfile.open(ARCHIVE)
-    tar.extractall(path=os.path.dirname(ARCHIVE))
-    tar.close()
+    # The archive is created only on swarming. Local checkouts have the
+    # data folder.
+    if os.path.exists(ARCHIVE):
+      print "Extracting archive..."
+      tar = tarfile.open(ARCHIVE)
+      tar.extractall(path=os.path.dirname(ARCHIVE))
+      tar.close()
 
 
 def GetSuite(name, root):