Oilpan: add missing leftmost trace()s for GC mixins.

For classes that are non-abstract (in a Blink sense) and inherit
from GarbageCollectedMixin, add a missing local trace() override.
This so as to insist on there being a trace() in the leftmost vtbl.

R=
BUG=340522

Review URL: https://codereview.chromium.org/835363003

git-svn-id: svn://svn.chromium.org/blink/trunk@187945 bbb929c8-8fbe-4397-9dbb-9b2b20218538
19 files changed
tree: df979706c8fc5d7eeea0d7f79f88063ae4ee4fb2
  1. third_party/