Let test runner rerun failures to test for flakes.

tools/testrunner/objects/context.py

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 11 matching lines @@
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 
 class Context():
   def __init__(self, arch, mode, shell_dir, mode_flags, verbose, timeout,
                isolates, command_prefix, extra_flags, noi18n, random_seed,
-               no_sorting):
+               no_sorting, rerun_failures_count, rerun_failures_max):
     self.arch = arch
     self.mode = mode
     self.shell_dir = shell_dir
     self.mode_flags = mode_flags
     self.verbose = verbose
     self.timeout = timeout
     self.isolates = isolates
     self.command_prefix = command_prefix
     self.extra_flags = extra_flags
     self.noi18n = noi18n
     self.random_seed = random_seed
     self.no_sorting = no_sorting
+    self.rerun_failures_count = rerun_failures_count
+    self.rerun_failures_max = rerun_failures_max
 
   def Pack(self):
     return [self.arch, self.mode, self.mode_flags, self.timeout, self.isolates,
             self.command_prefix, self.extra_flags, self.noi18n,
-            self.random_seed, self.no_sorting]
+            self.random_seed, self.no_sorting, self.rerun_failures_count,
+            self.rerun_failures_max]
 
   @staticmethod
   def Unpack(packed):
     # For the order of the fields, refer to Pack() above.
     return Context(packed[0], packed[1], None, packed[2], False,
                    packed[3], packed[4], packed[5], packed[6], packed[7],
-                   packed[8], packed[9])
+                   packed[8], packed[9], packed[10], packed[11])