Update WebKit to r93846.

DEPS

 vars = {
   # Use this googlecode_url variable only if there is an internal mirror for it.
   # If you do not know, use the full path while defining your new deps entry.
   "googlecode_url": "http://%s.googlecode.com/svn",
   "webkit_trunk": "http://svn.webkit.org/repository/webkit/trunk",
   "nacl_trunk": "http://src.chromium.org/native_client/trunk",
-  "webkit_revision": "93781",
+  "webkit_revision": "93846",
   "chromium_git": "http://git.chromium.org/git",
   "swig_revision": "69281",
   "nacl_revision": "6539",
   # After changing nacl_revision, run 'glient sync' and check native_client/DEPS
   # to update other nacl_*_revision's.
   # TODO(brettw) We should use the "From" syntax to avoid hardcoding the
   # revisions here, but it makes checkdeps confused. We should fix checkdeps.
   "nacl_tools_revision": "5360",  # native_client/DEPS: tools_rev
 
   # These hashes need to be updated when nacl_toolchain_revision is changed.
@@ skipping 397 matching lines @@
          "--file-hash", "linux_x86_newlib",
              Var("nacl_toolchain_linux_x86_newlib_hash"),
     ],
   },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",
     "action": ["python", "src/build/gyp_chromium"],
   },
 ]