[heap] Remove unnecessary marking specializations

src/heap/incremental-marking.cc

Index: src/heap/incremental-marking.cc
diff --git a/src/heap/incremental-marking.cc b/src/heap/incremental-marking.cc
index d091efb3aaa3a6b2648b7ac9ee830fa5f400de56..b1b50620ee069aa7583b88417666bb73cb4b7394 100644
--- a/src/heap/incremental-marking.cc
+++ b/src/heap/incremental-marking.cc
@@ -179,7 +179,6 @@ class IncrementalMarkingMarkingVisitor
     StaticMarkingVisitor<IncrementalMarkingMarkingVisitor>::Initialize();
     table_.Register(kVisitFixedArray, &VisitFixedArrayIncremental);
     table_.Register(kVisitNativeContext, &VisitNativeContextIncremental);
-    table_.Register(kVisitJSRegExp, &VisitJSRegExp);
   }
 
   static const int kProgressBarScanningChunk = 32 * 1024;