VM: Make precompiler process constants/fields only once, avoid using pool.InfoAt()

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/become.h"
@@ skipping 11584 matching lines @@
   return result.raw();
 }
 
 
 void ObjectPool::set_info_array(const TypedData& info_array) const {
   StorePointer(&raw_ptr()->info_array_, info_array.raw());
 }
 
 
 ObjectPool::EntryType ObjectPool::InfoAt(intptr_t index) const {
-  const TypedData& array = TypedData::Handle(info_array());
-  return static_cast<EntryType>(array.GetInt8(index));
+  ObjectPoolInfo pool_info(*this);
+  return pool_info.InfoAt(index);
 }
 
 
 const char* ObjectPool::ToCString() const {
   Zone* zone = Thread::Current()->zone();
   return zone->PrintToString("ObjectPool len:%" Pd, Length());
 }
 
 
 void ObjectPool::DebugPrint() const {
@@ skipping 11149 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart