[Interpreter] Enable tracing of bytecode handler dispatches.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index c23c1a4a9c722f0839fd4ca4976c41e90b10cda0..11ca120adfae670be3af89f2e7d06d47e9078d1a 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -41,6 +41,7 @@
 #include "src/base/platform/platform.h"
 #include "src/base/sys-info.h"
 #include "src/basic-block-profiler.h"
+#include "src/interpreter/interpreter.h"
 #include "src/snapshot/natives.h"
 #include "src/utils.h"
 #include "src/v8.h"
@@ -1312,6 +1313,13 @@ void Shell::OnExit(v8::Isolate* isolate) {
            "-------------+\n");
     delete [] counters;
   }
+
+  if (i::FLAG_trace_ignition_dispatches) {
+    reinterpret_cast<i::Isolate*>(isolate)
+        ->interpreter()
+        ->WriteDispatchCounters();
+  }
+
   delete counters_file_;
   delete counter_map_;
 #endif  // !V8_SHARED