Ensure black and gray objects are kept around by scavenger

src/heap/gc-tracer.h

Index: src/heap/gc-tracer.h
diff --git a/src/heap/gc-tracer.h b/src/heap/gc-tracer.h
index ed07750a4a91464701692e20943521b378417388..9afba8eb09cff54c12a3ed6160914d5693231c4a 100644
--- a/src/heap/gc-tracer.h
+++ b/src/heap/gc-tracer.h
@@ -59,54 +59,55 @@ inline BytesAndDuration MakeBytesAndDuration(uint64_t bytes, double duration) {
 
 enum ScavengeSpeedMode { kForAllObjects, kForSurvivedObjects };
 
-#define TRACER_SCOPES(F)                           \
-  F(EXTERNAL_WEAK_GLOBAL_HANDLES)                  \
-  F(MC_CLEAR)                                      \
-  F(MC_CLEAR_CODE_FLUSH)                           \
-  F(MC_CLEAR_DEPENDENT_CODE)                       \
-  F(MC_CLEAR_GLOBAL_HANDLES)                       \
-  F(MC_CLEAR_MAPS)                                 \
-  F(MC_CLEAR_SLOTS_BUFFER)                         \
-  F(MC_CLEAR_STORE_BUFFER)                         \
-  F(MC_CLEAR_STRING_TABLE)                         \
-  F(MC_CLEAR_WEAK_CELLS)                           \
-  F(MC_CLEAR_WEAK_COLLECTIONS)                     \
-  F(MC_CLEAR_WEAK_LISTS)                           \
-  F(MC_EVACUATE)                                   \
-  F(MC_EVACUATE_CANDIDATES)                        \
-  F(MC_EVACUATE_CLEAN_UP)                          \
-  F(MC_EVACUATE_COPY)                              \
-  F(MC_EVACUATE_UPDATE_POINTERS)                   \
-  F(MC_EVACUATE_UPDATE_POINTERS_TO_EVACUATED)      \
-  F(MC_EVACUATE_UPDATE_POINTERS_TO_NEW)            \
-  F(MC_EVACUATE_UPDATE_POINTERS_WEAK)              \
-  F(MC_EXTERNAL_EPILOGUE)                          \
-  F(MC_EXTERNAL_PROLOGUE)                          \
-  F(MC_FINISH)                                     \
-  F(MC_INCREMENTAL_FINALIZE)                       \
-  F(MC_INCREMENTAL_EXTERNAL_EPILOGUE)              \
-  F(MC_INCREMENTAL_EXTERNAL_PROLOGUE)              \
-  F(MC_MARK)                                       \
-  F(MC_MARK_FINISH_INCREMENTAL)                    \
-  F(MC_MARK_PREPARE_CODE_FLUSH)                    \
-  F(MC_MARK_ROOTS)                                 \
-  F(MC_MARK_WEAK_CLOSURE)                          \
-  F(MC_MARK_WEAK_CLOSURE_EPHEMERAL)                \
-  F(MC_MARK_WEAK_CLOSURE_WEAK_HANDLES)             \
-  F(MC_MARK_WEAK_CLOSURE_WEAK_ROOTS)               \
-  F(MC_MARK_WEAK_CLOSURE_HARMONY)                  \
-  F(MC_SWEEP)                                      \
-  F(MC_SWEEP_CODE)                                 \
-  F(MC_SWEEP_MAP)                                  \
-  F(MC_SWEEP_OLD)                                  \
-  F(SCAVENGER_CODE_FLUSH_CANDIDATES)               \
-  F(SCAVENGER_EXTERNAL_EPILOGUE)                   \
-  F(SCAVENGER_EXTERNAL_PROLOGUE)                   \
-  F(SCAVENGER_OBJECT_GROUPS)                       \
-  F(SCAVENGER_OLD_TO_NEW_POINTERS)                 \
-  F(SCAVENGER_ROOTS)                               \
-  F(SCAVENGER_SCAVENGE)                            \
-  F(SCAVENGER_SEMISPACE)                           \
+#define TRACER_SCOPES(F)                      \
+  F(EXTERNAL_WEAK_GLOBAL_HANDLES)             \
+  F(MC_CLEAR)                                 \
+  F(MC_CLEAR_CODE_FLUSH)                      \
+  F(MC_CLEAR_DEPENDENT_CODE)                  \
+  F(MC_CLEAR_GLOBAL_HANDLES)                  \
+  F(MC_CLEAR_MAPS)                            \
+  F(MC_CLEAR_SLOTS_BUFFER)                    \
+  F(MC_CLEAR_STORE_BUFFER)                    \
+  F(MC_CLEAR_STRING_TABLE)                    \
+  F(MC_CLEAR_WEAK_CELLS)                      \
+  F(MC_CLEAR_WEAK_COLLECTIONS)                \
+  F(MC_CLEAR_WEAK_LISTS)                      \
+  F(MC_EVACUATE)                              \
+  F(MC_EVACUATE_CANDIDATES)                   \
+  F(MC_EVACUATE_CLEAN_UP)                     \
+  F(MC_EVACUATE_COPY)                         \
+  F(MC_EVACUATE_UPDATE_POINTERS)              \
+  F(MC_EVACUATE_UPDATE_POINTERS_TO_EVACUATED) \
+  F(MC_EVACUATE_UPDATE_POINTERS_TO_NEW)       \
+  F(MC_EVACUATE_UPDATE_POINTERS_WEAK)         \
+  F(MC_EXTERNAL_EPILOGUE)                     \
+  F(MC_EXTERNAL_PROLOGUE)                     \
+  F(MC_FINISH)                                \
+  F(MC_INCREMENTAL_FINALIZE)                  \
+  F(MC_INCREMENTAL_EXTERNAL_EPILOGUE)         \
+  F(MC_INCREMENTAL_EXTERNAL_PROLOGUE)         \
+  F(MC_MARK)                                  \
+  F(MC_MARK_FINISH_INCREMENTAL)               \
+  F(MC_MARK_PREPARE_CODE_FLUSH)               \
+  F(MC_MARK_ROOTS)                            \
+  F(MC_MARK_WEAK_CLOSURE)                     \
+  F(MC_MARK_WEAK_CLOSURE_EPHEMERAL)           \
+  F(MC_MARK_WEAK_CLOSURE_WEAK_HANDLES)        \
+  F(MC_MARK_WEAK_CLOSURE_WEAK_ROOTS)          \
+  F(MC_MARK_WEAK_CLOSURE_HARMONY)             \
+  F(MC_SWEEP)                                 \
+  F(MC_SWEEP_CODE)                            \
+  F(MC_SWEEP_MAP)                             \
+  F(MC_SWEEP_OLD)                             \
+  F(SCAVENGER_CODE_FLUSH_CANDIDATES)          \
+  F(SCAVENGER_EXTERNAL_EPILOGUE)              \
+  F(SCAVENGER_EXTERNAL_PROLOGUE)              \
+  F(SCAVENGER_OBJECT_GROUPS)                  \
+  F(SCAVENGER_OLD_TO_NEW_POINTERS)            \
+  F(SCAVENGER_OBJECTS_MARKED_BY_MARK_COMPACT) \
+  F(SCAVENGER_ROOTS)                          \
+  F(SCAVENGER_SCAVENGE)                       \
+  F(SCAVENGER_SEMISPACE)                      \
   F(SCAVENGER_WEAK)
 
 #define TRACE_GC(tracer, scope_id)                             \