Roll PDFium ae2d47b..51cf5bc

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 41 matching lines @@
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
   'angle_revision': 'e73a1e847bbb984ae7c93bceee56b000fd1067f2',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling build tools
   # and whatever else without interference from each other.
   'buildtools_revision': 'ef7f1f539cff0441c4401d8c052e54cfd01bff07',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling PDFium
   # and whatever else without interference from each other.
-  'pdfium_revision': 'ae2d47b22d213cb36a66326c3167cfbbae90b9d4',
+  'pdfium_revision': '51cf5bc00dfa3033523355e3e74f3a47f7e46682',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling openmax_dl
   # and whatever else without interference from each other.
   'openmax_dl_revision': '37b900ccc45cfab71faf4fd332df15369766b94c',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.
   'boringssl_revision': '63fa118f3a3d065adb6ca17227bb9e407ffadccb',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling nss
@@ skipping 734 matching lines @@
     'pattern': '.',
     'action': [
         'python',
         'src/tools/check_git_config.py',
         '--running-as-hook',
     ],
   },
 ]