Update V8 to version 3.20.13.

TBR=jkummerow@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22378002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@215868 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -32,7 +32,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and V8 without interference from each other.
-  "v8_revision": "16053",
+  "v8_revision": "16065",
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling WebRTC
   # and V8 without interference from each other.