Collect debugging info for catch clauses

runtime/vm/raw_object.cc

Index: runtime/vm/raw_object.cc
===================================================================
--- runtime/vm/raw_object.cc	(revision 17099)
+++ runtime/vm/raw_object.cc	(working copy)
@@ -226,7 +226,7 @@
       case kExceptionHandlersCid: {
         const RawExceptionHandlers* raw_handlers =
             reinterpret_cast<const RawExceptionHandlers*>(this);
-        intptr_t num_handlers = Smi::Value(raw_handlers->ptr()->length_);
+        intptr_t num_handlers = raw_handlers->ptr()->length_;
         instance_size = ExceptionHandlers::InstanceSize(num_handlers);
         break;
       }
@@ -523,9 +523,10 @@
 intptr_t RawExceptionHandlers::VisitExceptionHandlersPointers(
     RawExceptionHandlers* raw_obj, ObjectPointerVisitor* visitor) {
   RawExceptionHandlers* obj = raw_obj->ptr();
-  intptr_t length = Smi::Value(obj->length_);
-  visitor->VisitPointer(reinterpret_cast<RawObject**>(&obj->length_));
-  return ExceptionHandlers::InstanceSize(length);
+  intptr_t len = obj->length_;
+  visitor->VisitPointer(
+      reinterpret_cast<RawObject**>(&obj->handled_types_data_));
+  return ExceptionHandlers::InstanceSize(len);
 }