Roll src/third_party/WebKit 60b7b03:15081cc (svn 195513:195519)

Summary of changes available at:
https://chromium.googlesource.com/chromium/blink/+log/60b7b03..15081cc

TBR=kbr@chromium.org,hiroshige@chromium.org

Review URL: https://codereview.chromium.org/1137643006

Cr-Commit-Position: refs/heads/master@{#330493}

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': '60b7b03c3866fc11ea58fa33de81e489c1e0a342', # from svn revision 195513
+  'webkit_revision': '15081cc41c24517f3d61259794b866a25d625475', # from svn revision 195519
   'chromium_git': 'https://chromium.googlesource.com',
   'chromiumos_git': 'https://chromium.googlesource.com/chromiumos',
   'pdfium_git': 'https://pdfium.googlesource.com',