Refactor skipped code functions interface.

runtime/vm/raw_object.cc

Index: runtime/vm/raw_object.cc
diff --git a/runtime/vm/raw_object.cc b/runtime/vm/raw_object.cc
index 88ebb5bab3ff03c916de2e400dd63d8ece6512a7..47e9306c47c11bb85cdb82a4d55fe9622e866df2 100644
--- a/runtime/vm/raw_object.cc
+++ b/runtime/vm/raw_object.cc
@@ -443,14 +443,14 @@ intptr_t RawFunction::VisitFunctionPointers(RawFunction* raw_obj,
     visitor->VisitPointer(
         reinterpret_cast<RawObject**>(&raw_obj->ptr()->instructions_));
   } else {
-    visitor->skipped_code_functions()->Add(raw_obj);
+    visitor->add_skipped_code_function(raw_obj);
   }
 
   if (ShouldVisitCode(raw_obj->ptr()->unoptimized_code_)) {
     visitor->VisitPointer(
         reinterpret_cast<RawObject**>(&raw_obj->ptr()->unoptimized_code_));
   } else {
-    visitor->skipped_code_functions()->Add(raw_obj);
+    visitor->add_skipped_code_function(raw_obj);
   }
   return Function::InstanceSize();
 }