Oilpan: use Member<> for FilterEffect's filter reference.

Both FilterEffect and SkiaImageFilterBuilder keep assumed
strong references to GCed objects, but without tracing them.
Add the required Member<> to these references and trace
them (when explicitly needed.)

R=haraken
BUG=340522

Review URL: https://codereview.chromium.org/791613002

git-svn-id: svn://svn.chromium.org/blink/trunk@186767 bbb929c8-8fbe-4397-9dbb-9b2b20218538
4 files changed
tree: cab7cb7e82ae58ac54cf830e48ba7651c4f2becd
  1. third_party/