Add exception handler cache to isolate

runtime/vm/heap.cc

Index: runtime/vm/heap.cc
diff --git a/runtime/vm/heap.cc b/runtime/vm/heap.cc
index d8ce15740a980e1d6327333eb41a7baa3d1013b4..78bd07b428bf5611832043049271a4258c5fb001 100644
--- a/runtime/vm/heap.cc
+++ b/runtime/vm/heap.cc
@@ -402,6 +402,8 @@ void Heap::CollectOldSpaceGarbage(Thread* thread,
     RecordAfterGC(kOld);
     PrintStats();
     NOT_IN_PRODUCT(PrintStatsToTimeline(&tds));
+    // Some Code objects may have been collected so invalidate handler cache.
+    thread->isolate()->handler_info_cache.Clear();

[Florian Schneider, 2017/02/08 21:34:05]

Can we only invalidate if there was a code GC, and not at every old-space GC?

[Dmitry Olshansky, 2017/02/09 17:54:34]

Asked Slava and basically we can't know if there was Code GC or not.

     EndOldSpaceGC();
   }
 }