[serializer] add options to compile eagerly and pre-age for code cache.

src/snapshot/deserializer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/snapshot/deserializer.h"
 
 #include "src/bootstrapper.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
 #include "src/macro-assembler.h"
@@ skipping 23 matching lines @@
   while (it.has_next()) {
     Page* p = it.next();
     Assembler::FlushICache(isolate_, p->area_start(),
                            p->area_end() - p->area_start());
   }
 }
 
 void Deserializer::FlushICacheForNewCodeObjects() {
   DCHECK(deserializing_user_code_);
   for (Code* code : new_code_objects_) {
+    if (FLAG_serialize_age_code) code->PreAge(isolate_);
     Assembler::FlushICache(isolate_, code->instruction_start(),
                            code->instruction_size());
   }
 }
 
 bool Deserializer::ReserveSpace() {
 #ifdef DEBUG
   for (int i = NEW_SPACE; i < kNumberOfSpaces; ++i) {
     CHECK(reservations_[i].length() > 0);
   }
@@ skipping 750 matching lines @@
 
       default:
         CHECK(false);
     }
   }
   CHECK_EQ(limit, current);
   return true;
 }
 }  // namespace internal
 }  // namespace v8