GitLab

Blink r187605 https://crrev.com/804873004 introduced DEFINE_TRACE macros,
which dedupes trace(Visitor*) and trace(InlinedGlobalMarkingVisitor) by
using template method:
template<typename VisitorDispatcher> void traceImpl(VisitorDispatcher);

This CL updates the GC plugin, so that it:
- recognizes traceImpl method, and mark trace(field) calls made inside.
- recognizes trace method that just delegate to traceImpl, and skip its processing.
  - e.g.) void trace(Visitor* visitor) { traceImpl(visitor); }

BUG=420515

Review URL: https://codereview.chromium.org/824853003

Cr-Commit-Position: refs/heads/master@{#309627}