Update V8 to version 5.2.252.

DEPS

 # This file is used to manage the dependencies of the Chromium src repo. It is
 # used by gclient to determine what version of each dependency to check out, and
 # where.
 #
 # For more information, please refer to the official documentation:
 #   https://sites.google.com/a/chromium.org/dev/developers/how-tos/get-the-code
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 #
@@ skipping 25 matching lines @@
   # the commit queue can handle CLs rolling sfntly
   # and whatever else without interference from each other.
   'sfntly_revision': '130f832eddf98467e6578b548cb74ce17d04a26d',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
   'skia_revision': '0938befe5d1e36df820a67e5dc554b462388d46b',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.
-  'v8_revision': '55251cefb8b149f88914dbc401aa302936b129c9',
+  'v8_revision': '31b1ce14dcfb2badd93140389be50c13e0916b5d',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling swarming_client
   # and whatever else without interference from each other.
   'swarming_revision': 'df6e95e7669883c8fe9ef956c69a544154701a49',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
   'angle_revision': 'a314b61c16be864567920bab145881576457205e',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling build tools
@@ skipping 789 matching lines @@
                'src/build/android/download_doclava.py',
     ],
   },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     'name': 'gyp',
     'pattern': '.',
     'action': ['python', 'src/build/gyp_chromium', '--running-as-hook'],
   },
 ]