Roll src/third_party/WebKit 2df2b3e:23bf4d4 (svn 187099:187101)

Summary of changes available at:
https://chromium.googlesource.com/chromium/blink/+log/2df2b3e..23bf4d4

TBR=

Review URL: https://codereview.chromium.org/787253007

Cr-Commit-Position: refs/heads/master@{#308293}

DEPS

@@ -36,7 +36,7 @@ vars = {
   'libcxx_revision': '48198f9110397fff47fe7c37cbfa296be7d44d3d',
   'libcxxabi_revision': '4ad1009ab3a59fa7a6896d74d5e4de5885697f95',
   'webkit_trunk': 'http://src.chromium.org/blink/trunk',
-  'webkit_revision': '2df2b3e52cd783c1adb3eeb96dea89deda93220e', # from svn revision 187099
+  'webkit_revision': '23bf4d456656dca0d1484480e536d959466008b1', # from svn revision 187101
   'chromium_git': 'https://chromium.googlesource.com',
   'chromiumos_git': 'https://chromium.googlesource.com/chromiumos',
   'pdfium_git': 'https://pdfium.googlesource.com',