Make 'ASAN' configurable in test status file.

tools/run-tests.py

Index: tools/run-tests.py
diff --git a/tools/run-tests.py b/tools/run-tests.py
index e032a55f508bbadd6d950ccd4bc3358848f893d7..f905c03d3f63789d39254ec978966e830f769653 100755
--- a/tools/run-tests.py
+++ b/tools/run-tests.py
@@ -99,6 +99,9 @@ def BuildOptions():
   result.add_option("--arch-and-mode",
                     help="Architecture and mode in the format 'arch.mode'",
                     default=None)
+  result.add_option("--asan",
+                    help="Regard test expectations for ASAN",
+                    default=False, action="store_true")
   result.add_option("--buildbot",
                     help="Adapt to path structure used on buildbots",
                     default=False, action="store_true")
@@ -386,6 +389,7 @@ def Execute(arch, mode, args, options, suites, workspace):
   # Find available test suites and read test cases from them.
   variables = {
     "arch": arch,
+    "asan": options.asan,
     "deopt_fuzzer": False,
     "gc_stress": options.gc_stress,
     "isolates": options.isolates,