In file included from traceimpl_dependent_scope.cpp:5:
./traceimpl_dependent_scope.h:37:3: warning: [blink-gc] Base class 'Base<int>' of derived class 'DerivedMissingTrace<int>' requires tracing.
  void Trace(Visitor* visitor) const override {
  ^
./traceimpl_dependent_scope.h:51:3: warning: [blink-gc] Base class 'X' of derived class 'MixinMissingTrace<blink::X>' requires tracing.
  void Trace(Visitor* visitor) const override {
  ^
./traceimpl_dependent_scope.h:68:3: warning: [blink-gc] Base class 'Y' of derived class 'MixinTwoBasesMissingTrace<blink::X, blink::Y>' requires tracing.
  void Trace(Visitor* visitor) const override {
  ^
3 warnings generated.