[re2] Roll re2 4be7a14..5185d85.

Bug: 790735
Change-Id: Ibf368a23b402dbe12c03afaed4032267abe52794
Reviewed-on: https://chromium-review.googlesource.com/808991Reviewed-by: Max Moroz <mmoroz@chromium.org>
Reviewed-by: Abhishek Arya <inferno@chromium.org>
Commit-Queue: Max Moroz <mmoroz@chromium.org>
Commit-Queue: Abhishek Arya <inferno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521743}

DEPS

@@ -568,7 +568,7 @@ deps = {
     Var('chromium_git') + '/external/github.com/google/pywebsocket.git' + '@' + '2d7b73c3acbd0f41dcab487ae5c97c6feae06ce2',
 
   'src/third_party/re2/src':
-    Var('chromium_git') + '/external/github.com/google/re2.git' + '@' + '4be7a14432ff0a2ed88fd884fd76a63f0a3a6127',
+    Var('chromium_git') + '/external/github.com/google/re2.git' + '@' + '5185d85264d23cfae4b38e2703703e9a4c8e974c',
 
   'src/third_party/requests/src': {
       'url': Var('chromium_git') + '/external/github.com/kennethreitz/requests.git' + '@' + 'f172b30356d821d180fa4ecfa3e71c7274a32de4',