Roll src/third_party/WebKit 6a1bbc3:3130d67 (svn 189304:189306)

Summary of changes available at:
https://chromium.googlesource.com/chromium/blink/+log/6a1bbc3..3130d67

TBR=

Review URL: https://codereview.chromium.org/891203002

Cr-Commit-Position: refs/heads/master@{#314088}

DEPS

@@ -34,7 +34,7 @@ vars = {
   'llvm_url': 'http://src.chromium.org/llvm-project',
   'llvm_git': 'https://llvm.googlesource.com',
   'webkit_trunk': 'http://src.chromium.org/blink/trunk',
-  'webkit_revision': '6a1bbc3f0b692e41fdbcf7ee78bae22e24107543', # from svn revision 189304
+  'webkit_revision': '3130d6795388a887bf995d48eefc31e4dad30013', # from svn revision 189306
   'chromium_git': 'https://chromium.googlesource.com',
   'chromiumos_git': 'https://chromium.googlesource.com/chromiumos',
   'pdfium_git': 'https://pdfium.googlesource.com',