[heap] Add detailed timers to --trace-gc-nvp MC marking phase.

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 e96dfd4a80a6cfc7c642a94413044fb1b4e333f3..a9205585c674064cca457366b14125150270c13e 100644
--- a/src/heap/gc-tracer.h
+++ b/src/heap/gc-tracer.h
@@ -99,6 +99,16 @@ class GCTracer {
     enum ScopeId {
       EXTERNAL,
       MC_MARK,
+      MC_MARK_FINISH_INCREMENTAL,
+      MC_MARK_PREPARE_CODE_FLUSH,
+      MC_MARK_ROOT,
+      MC_MARK_TOPOPT,
+      MC_MARK_RETAIN_MAPS,
+      MC_MARK_WEAK_CLOSURE,
+      MC_MARK_STRING_TABLE,
+      MC_MARK_WEAK_REFERENCES,
+      MC_MARK_GLOBAL_HANDLES,
+      MC_MARK_CODE_FLUSH,
       MC_SWEEP,
       MC_SWEEP_NEWSPACE,
       MC_SWEEP_OLDSPACE,