Conditional flags for tests - set JS stack size for simulators.

tools/testrunner/objects/testcase.py

Index: tools/testrunner/objects/testcase.py
diff --git a/tools/testrunner/objects/testcase.py b/tools/testrunner/objects/testcase.py
index ca826067c7c8f5bbc87b641f8d967117b1a5eede..6c5508274314f9cde95efe28dad2d79415d0899b 100644
--- a/tools/testrunner/objects/testcase.py
+++ b/tools/testrunner/objects/testcase.py
@@ -29,10 +29,10 @@
 from . import output
 
 class TestCase(object):
-  def __init__(self, suite, path, flags=[], dependency=None):
-    self.suite = suite  # TestSuite object
-    self.path = path    # string, e.g. 'div-mod', 'test-api/foo'
-    self.flags = flags  # list of strings, flags specific to this test case
+  def __init__(self, suite, path, flags=None, dependency=None):
+    self.suite = suite        # TestSuite object
+    self.path = path          # string, e.g. 'div-mod', 'test-api/foo'
+    self.flags = flags or []  # list of strings, flags specific to this test
     self.dependency = dependency  # |path| for testcase that must be run first
     self.outcomes = None
     self.output = None