Oilpan: tidy StylePropertySerializer's handling of GCed objects.

Add the required annotations + correctly represent and trace embedded
StylePropertySet references.

R=haraken
BUG=509911

Review URL: https://codereview.chromium.org/1278143002

git-svn-id: svn://svn.chromium.org/blink/trunk@200164 bbb929c8-8fbe-4397-9dbb-9b2b20218538
2 files changed
tree: ccbf67e7485923eaeabc7dfcb1f4121a2febeaf4
  1. third_party/